diff --git a/cmd/cmd.go b/cmd/cmd.go
index 4ba466bd7..eca7ae8d5 100644
--- a/cmd/cmd.go
+++ b/cmd/cmd.go
@@ -353,33 +353,37 @@ func StartNode(workingDir string, passwordFetcher func(*wallet.Wallet) (string,
 	if err != nil {
 		return nil, nil, err
 	}
-	allValAddrs := walletInstance.AllValidatorAddresses()
 
-	if len(allValAddrs) < 1 || len(allValAddrs) > 32 {
-		return nil, nil, fmt.Errorf("number of validators must be between 1 and 32, but it's %d",
-			len(allValAddrs))
+	valAddrsInfo := walletInstance.AllValidatorAddresses()
+	if len(valAddrsInfo) == 0 {
+		return nil, nil, fmt.Errorf("no validator addresses found in the wallet")
+	}
+
+	if len(valAddrsInfo) > 32 {
+		PrintWarnMsgf("wallet has more than 32 validator addresses, only the first 32 will be used")
+		valAddrsInfo = valAddrsInfo[:32]
 	}
 
 	if len(conf.Node.RewardAddresses) > 0 &&
-		len(conf.Node.RewardAddresses) != len(allValAddrs) {
-		return nil, nil, fmt.Errorf("reward addresses should be %v", len(allValAddrs))
+		len(conf.Node.RewardAddresses) != len(valAddrsInfo) {
+		return nil, nil, fmt.Errorf("reward addresses should be %v", len(valAddrsInfo))
 	}
 
-	validatorAddrs := make([]string, len(allValAddrs))
-	for i := 0; i < len(validatorAddrs); i++ {
-		valAddr, _ := crypto.AddressFromString(allValAddrs[i].Address)
+	valAddrs := make([]string, len(valAddrsInfo))
+	for i := 0; i < len(valAddrs); i++ {
+		valAddr, _ := crypto.AddressFromString(valAddrsInfo[i].Address)
 		if !valAddr.IsValidatorAddress() {
-			return nil, nil, fmt.Errorf("invalid validator address: %s", allValAddrs[i].Address)
+			return nil, nil, fmt.Errorf("invalid validator address: %s", valAddrsInfo[i].Address)
 		}
-		validatorAddrs[i] = valAddr.String()
+		valAddrs[i] = valAddr.String()
 	}
 
-	valKeys := make([]*bls.ValidatorKey, len(allValAddrs))
+	valKeys := make([]*bls.ValidatorKey, len(valAddrsInfo))
 	password, ok := passwordFetcher(walletInstance)
 	if !ok {
 		return nil, nil, fmt.Errorf("aborted")
 	}
-	prvKeys, err := walletInstance.PrivateKeys(password, validatorAddrs)
+	prvKeys, err := walletInstance.PrivateKeys(password, valAddrs)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -388,21 +392,25 @@ func StartNode(workingDir string, passwordFetcher func(*wallet.Wallet) (string,
 	}
 
 	// Create reward addresses
-	rewardAddrs := make([]crypto.Address, 0, len(allValAddrs))
+	rewardAddrs := make([]crypto.Address, 0, len(valAddrsInfo))
 	if len(conf.Node.RewardAddresses) != 0 {
 		for _, addrStr := range conf.Node.RewardAddresses {
 			addr, _ := crypto.AddressFromString(addrStr)
 			rewardAddrs = append(rewardAddrs, addr)
 		}
 	} else {
-		for i := 0; i < len(allValAddrs); i++ {
-			valAddrPath, _ := addresspath.NewPathFromString(allValAddrs[i].Path)
-			accAddrPath := addresspath.NewPath(valAddrPath.Purpose(), valAddrPath.CoinType(),
-				uint32(crypto.AddressTypeValidator)+hdkeychain.HardenedKeyStart, valAddrPath.AddressIndex())
+		for i := 0; i < len(valAddrsInfo); i++ {
+			valAddrPath, _ := addresspath.NewPathFromString(valAddrsInfo[i].Path)
+			accAddrPath := addresspath.NewPath(
+				valAddrPath.Purpose(),
+				valAddrPath.CoinType(),
+				uint32(crypto.AddressTypeBLSAccount)+hdkeychain.HardenedKeyStart,
+				valAddrPath.AddressIndex())
 
 			addrInfo := walletInstance.AddressFromPath(accAddrPath.String())
 			if addrInfo == nil {
-				return nil, nil, fmt.Errorf("unable to find reward address for: %s", allValAddrs[i].Address)
+				return nil, nil, fmt.Errorf("unable to find reward address for: %s [%s]",
+					valAddrsInfo[i].Address, accAddrPath)
 			}
 
 			addr, _ := crypto.AddressFromString(addrInfo.Address)
@@ -410,6 +418,13 @@ func StartNode(workingDir string, passwordFetcher func(*wallet.Wallet) (string,
 		}
 	}
 
+	// Check if reward addresses are account address
+	for _, addr := range rewardAddrs {
+		if !addr.IsAccountAddress() {
+			return nil, nil, fmt.Errorf("reward address is not an account address: %s", addr)
+		}
+	}
+
 	nodeInstance, err := node.NewNode(gen, conf, valKeys, rewardAddrs)
 	if err != nil {
 		return nil, nil, err
diff --git a/wallet/addresspath/path.go b/wallet/addresspath/path.go
index 0e5d159bb..9e9457f40 100644
--- a/wallet/addresspath/path.go
+++ b/wallet/addresspath/path.go
@@ -17,6 +17,7 @@ func NewPath(indexes ...uint32) Path {
 	return p
 }
 
+// TODO: check the path should exactly 4 levels.
 func NewPathFromString(str string) (Path, error) {
 	sub := strings.Split(str, "/")
 	if sub[0] != "m" {
@@ -52,6 +53,8 @@ func (p Path) String() string {
 	return builder.String()
 }
 
+// TODO: we can add IsBLSPurpose or IsImportedPurpose functions
+
 func (p Path) Purpose() uint32 {
 	return p[0]
 }
diff --git a/wallet/vault/utils.go b/wallet/vault/utils.go
index 3d97c5fc4..82394df17 100644
--- a/wallet/vault/utils.go
+++ b/wallet/vault/utils.go
@@ -1,7 +1,9 @@
 package vault
 
 import (
+	"github.com/pactus-project/pactus/crypto/bls/hdkeychain"
 	"github.com/tyler-smith/go-bip39"
+	"golang.org/x/exp/constraints"
 )
 
 // GenerateMnemonic generates a new mnemonic (seed phrase) based on BIP-39
@@ -22,3 +24,8 @@ func CheckMnemonic(mnemonic string) error {
 	_, err := bip39.EntropyFromMnemonic(mnemonic)
 	return err
 }
+
+// H hardens the value 'i' by adding it to 0x80000000 (2^31).
+func H[T constraints.Integer](i T) uint32 {
+	return uint32(i) + hdkeychain.HardenedKeyStart
+}
diff --git a/wallet/vault/vault.go b/wallet/vault/vault.go
index 436b354b7..9483faa70 100644
--- a/wallet/vault/vault.go
+++ b/wallet/vault/vault.go
@@ -48,12 +48,8 @@ type AddressInfo struct {
 }
 
 const (
-	PurposeBLS12381                 = uint32(12381)
-	HardenedPurposeBLS12381         = PurposeBLS12381 + hdkeychain.HardenedKeyStart
-	PurposeImportPrivateKey         = uint32(65535)
-	HardenedPurposeImportPrivateKey = PurposeImportPrivateKey + hdkeychain.HardenedKeyStart
-	HardenedAddressTypeBLSAccount   = uint32(crypto.AddressTypeBLSAccount) + hdkeychain.HardenedKeyStart
-	HardenedAddressTypeValidator    = uint32(crypto.AddressTypeValidator) + hdkeychain.HardenedKeyStart
+	PurposeBLS12381         = uint32(12381)
+	PurposeImportPrivateKey = uint32(65535)
 )
 
 type Vault struct {
@@ -97,18 +93,18 @@ func CreateVaultFromMnemonic(mnemonic string, coinType uint32) (*Vault, error) {
 	enc := encrypter.NopeEncrypter()
 
 	xPubValidator, err := masterKey.DerivePath([]uint32{
-		12381 + hdkeychain.HardenedKeyStart,
-		coinType + hdkeychain.HardenedKeyStart,
-		uint32(crypto.AddressTypeValidator) + hdkeychain.HardenedKeyStart,
+		H(PurposeBLS12381),
+		H(coinType),
+		H(crypto.AddressTypeValidator),
 	})
 	if err != nil {
 		return nil, err
 	}
 
 	xPubAccount, err := masterKey.DerivePath([]uint32{
-		12381 + hdkeychain.HardenedKeyStart,
-		coinType + hdkeychain.HardenedKeyStart,
-		uint32(crypto.AddressTypeBLSAccount) + hdkeychain.HardenedKeyStart,
+		H(PurposeBLS12381),
+		H(coinType),
+		H(crypto.AddressTypeBLSAccount),
 	})
 	if err != nil {
 		return nil, err
@@ -222,22 +218,7 @@ func (v *Vault) AllValidatorAddresses() []AddressInfo {
 	addrs := make([]AddressInfo, 0, v.AddressCount()/2)
 	for _, addrInfo := range v.Addresses {
 		addrPath, _ := addresspath.NewPathFromString(addrInfo.Path)
-		if addrPath.AddressType()-hdkeychain.HardenedKeyStart == uint32(crypto.AddressTypeValidator) {
-			addrs = append(addrs, addrInfo)
-		}
-	}
-
-	v.SortAddressesByAddressIndex(addrs...)
-	v.SortAddressesByPurpose(addrs...)
-
-	return addrs
-}
-
-func (v *Vault) AllBLSAccountAddresses() []AddressInfo {
-	addrs := make([]AddressInfo, 0, v.AddressCount()/2)
-	for _, addrInfo := range v.Addresses {
-		addrPath, _ := addresspath.NewPathFromString(addrInfo.Path)
-		if addrPath.AddressType()-hdkeychain.HardenedKeyStart == uint32(crypto.AddressTypeBLSAccount) {
+		if addrPath.AddressType() == H(crypto.AddressTypeValidator) {
 			addrs = append(addrs, addrInfo)
 		}
 	}
@@ -252,7 +233,7 @@ func (v *Vault) AllImportedPrivateKeysAddresses() []AddressInfo {
 	addrs := make([]AddressInfo, 0, v.AddressCount()/2)
 	for _, addrInfo := range v.Addresses {
 		addrPath, _ := addresspath.NewPathFromString(addrInfo.Path)
-		if addrPath.Purpose() == HardenedPurposeImportPrivateKey {
+		if addrPath.Purpose() == H(PurposeImportPrivateKey) {
 			addrs = append(addrs, addrInfo)
 		}
 	}
@@ -331,17 +312,17 @@ func (v *Vault) ImportPrivateKey(password string, prv *bls.PrivateKey) error {
 		return ErrAddressExists
 	}
 
-	blsAccPathStr := addresspath.NewPath(HardenedPurposeImportPrivateKey,
-		v.CoinType+hdkeychain.HardenedKeyStart,
-		HardenedAddressTypeBLSAccount,
-		uint32(addressIndex)+hdkeychain.HardenedKeyStart).
-		String()
+	blsAccPathStr := addresspath.NewPath(
+		H(PurposeImportPrivateKey),
+		H(v.CoinType),
+		H(crypto.AddressTypeBLSAccount),
+		H(addressIndex)).String()
 
-	blsValidatorPathStr := addresspath.NewPath(HardenedPurposeImportPrivateKey,
-		v.CoinType+addresspath.HardenedKeyStart,
-		HardenedAddressTypeValidator,
-		uint32(addressIndex)+hdkeychain.HardenedKeyStart).
-		String()
+	blsValidatorPathStr := addresspath.NewPath(
+		H(PurposeImportPrivateKey),
+		H(v.CoinType),
+		H(crypto.AddressTypeValidator),
+		H(addressIndex)).String()
 
 	importedPrvLabelCounter := (len(v.AllImportedPrivateKeysAddresses()) / 2) + 1
 	v.Addresses[accAddr.String()] = AddressInfo{
@@ -390,12 +371,12 @@ func (v *Vault) PrivateKeys(password string, addrs []string) ([]crypto.PrivateKe
 			return nil, err
 		}
 
-		if path.CoinType()-hdkeychain.HardenedKeyStart != v.CoinType {
+		if path.CoinType() != H(v.CoinType) {
 			return nil, ErrInvalidCoinType
 		}
 
 		switch path.Purpose() {
-		case HardenedPurposeBLS12381:
+		case H(PurposeBLS12381):
 			seed, err := bip39.NewSeedWithErrorChecking(keyStore.MasterNode.Mnemonic, "")
 			if err != nil {
 				return nil, err
@@ -419,8 +400,9 @@ func (v *Vault) PrivateKeys(password string, addrs []string) ([]crypto.PrivateKe
 			}
 
 			keys[i] = prvKey
-		case HardenedPurposeImportPrivateKey:
+		case H(PurposeImportPrivateKey):
 			index := path.AddressIndex() - hdkeychain.HardenedKeyStart
+			// TODO: index out of range check
 			str := keyStore.ImportedKeys[index]
 			prv, err := bls.PrivateKeyFromString(str)
 			if err != nil {
@@ -504,12 +486,12 @@ func (v *Vault) AddressInfo(addr string) *AddressInfo {
 	}
 
 	// TODO it would be better to return error in future
-	if path.CoinType()-hdkeychain.HardenedKeyStart != v.CoinType {
+	if path.CoinType() != H(v.CoinType) {
 		return nil
 	}
 
 	switch path.Purpose() {
-	case HardenedPurposeBLS12381:
+	case H(PurposeBLS12381):
 		addr, err := crypto.AddressFromString(info.Address)
 		if err != nil {
 			return nil
@@ -543,7 +525,7 @@ func (v *Vault) AddressInfo(addr string) *AddressInfo {
 		}
 
 		info.PublicKey = blsPubKey.String()
-	case HardenedPurposeImportPrivateKey:
+	case H(PurposeImportPrivateKey):
 	default:
 		return nil
 	}
diff --git a/wallet/vault/vault_test.go b/wallet/vault/vault_test.go
index 232edaef5..c82776341 100644
--- a/wallet/vault/vault_test.go
+++ b/wallet/vault/vault_test.go
@@ -84,7 +84,7 @@ func TestAddressInfo(t *testing.T) {
 		path, _ := addresspath.NewPathFromString(info.Path)
 
 		switch path.Purpose() {
-		case HardenedPurposeBLS12381:
+		case H(PurposeBLS12381):
 			if addr.IsValidatorAddress() {
 				assert.Equal(t, info.Path, fmt.Sprintf("m/%d'/%d'/1'/%d",
 					PurposeBLS12381, td.vault.CoinType, path.AddressIndex()))
@@ -94,7 +94,7 @@ func TestAddressInfo(t *testing.T) {
 				assert.Equal(t, info.Path, fmt.Sprintf("m/%d'/%d'/2'/%d",
 					PurposeBLS12381, td.vault.CoinType, path.AddressIndex()))
 			}
-		case HardenedPurposeImportPrivateKey:
+		case H(PurposeImportPrivateKey):
 			if addr.IsValidatorAddress() {
 				assert.Equal(t, info.Path, fmt.Sprintf("m/%d'/%d'/1'/%d'",
 					PurposeImportPrivateKey, td.vault.CoinType, path.AddressIndex()-hdkeychain.HardenedKeyStart))
@@ -135,10 +135,10 @@ func TestAllValidatorAddresses(t *testing.T) {
 		path, _ := addresspath.NewPathFromString(info.Path)
 
 		switch path.Purpose() {
-		case HardenedPurposeBLS12381:
+		case H(PurposeBLS12381):
 			assert.Equal(t, info.Path, fmt.Sprintf("m/%d'/%d'/1'/%d",
 				PurposeBLS12381, td.vault.CoinType, path.AddressIndex()))
-		case HardenedPurposeImportPrivateKey:
+		case H(PurposeImportPrivateKey):
 			assert.Equal(t, info.Path, fmt.Sprintf("m/%d'/%d'/1'/%d'",
 				PurposeImportPrivateKey, td.vault.CoinType, path.AddressIndex()-hdkeychain.HardenedKeyStart))
 		}
@@ -155,40 +155,6 @@ func TestSortAllValidatorAddresses(t *testing.T) {
 	assert.Equal(t, "m/65535'/21888'/1'/0'", validatorAddrs[len(validatorAddrs)-1].Path)
 }
 
-func TestAllBLSAccountAddresses(t *testing.T) {
-	td := setup(t)
-
-	assert.Equal(t, td.vault.AddressCount(), 6)
-
-	blsAccountAddrs := td.vault.AllBLSAccountAddresses()
-	for _, i := range blsAccountAddrs {
-		info := td.vault.AddressInfo(i.Address)
-		assert.Equal(t, i.Address, info.Address)
-
-		path, _ := addresspath.NewPathFromString(info.Path)
-
-		switch path.Purpose() {
-		case HardenedPurposeBLS12381:
-			assert.Equal(t, info.Path, fmt.Sprintf("m/%d'/%d'/2'/%d",
-				PurposeBLS12381, td.vault.CoinType, path.AddressIndex()))
-		case HardenedPurposeImportPrivateKey:
-			assert.Equal(t, info.Path, fmt.Sprintf("m/%d'/%d'/2'/%d'",
-				PurposeImportPrivateKey, td.vault.CoinType, path.AddressIndex()-hdkeychain.HardenedKeyStart))
-		}
-	}
-}
-
-func TestSortAllBLSAccountAddresses(t *testing.T) {
-	td := setup(t)
-
-	assert.Equal(t, td.vault.AddressCount(), 6)
-
-	blsAccountAddrs := td.vault.AllBLSAccountAddresses()
-
-	assert.Equal(t, "m/12381'/21888'/2'/0", blsAccountAddrs[0].Path)
-	assert.Equal(t, "m/65535'/21888'/2'/0'", blsAccountAddrs[len(blsAccountAddrs)-1].Path)
-}
-
 func TestAddressFromPath(t *testing.T) {
 	td := setup(t)
 	assert.Equal(t, td.vault.AddressCount(), 6)
diff --git a/wallet/wallet_test.go b/wallet/wallet_test.go
index 873acfd36..d40ca173d 100644
--- a/wallet/wallet_test.go
+++ b/wallet/wallet_test.go
@@ -182,16 +182,25 @@ func TestInvalidAddress(t *testing.T) {
 	assert.Error(t, err)
 }
 
-// TODO: Fix later.
-// func TestImportPrivateKey(t *testing.T) {
-// 	td := setup(t)
+func TestImportPrivateKey(t *testing.T) {
+	td := setup(t)
+
+	_, prv := td.RandBLSKeyPair()
+	assert.NoError(t, td.wallet.ImportPrivateKey(td.password, prv))
+
+	pub := prv.PublicKeyNative()
+	accAddr := pub.AccountAddress().String()
+	valAddr := pub.AccountAddress().String()
 
-// 	_, prv := td.RandBLSKeyPair()
-// 	assert.NoError(t, td.wallet.ImportPrivateKey(td.password, prv))
+	assert.True(t, td.wallet.Contains(accAddr))
+	assert.True(t, td.wallet.Contains(valAddr))
 
-// 	addr := prv.PublicKeyNative().AccountAddress().String()
-// 	assert.True(t, td.wallet.Contains(addr))
-// }
+	accAddrInfo := td.wallet.AddressInfo(accAddr)
+	valAddrInfo := td.wallet.AddressInfo(accAddr)
+
+	assert.Equal(t, pub.String(), accAddrInfo.PublicKey)
+	assert.Equal(t, pub.String(), valAddrInfo.PublicKey)
+}
 
 func TestKeyInfo(t *testing.T) {
 	td := setup(t)