diff --git a/CHANGELOG.md b/CHANGELOG.md
index ae86311..e3c023d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 1.4.0
+
+* Fix blockcypher API
+
 ## 1.3.0
 
 * Include a constructor in the address for improved clarity and comprehension.
diff --git a/lib/src/provider/api_provider/api_provider.dart b/lib/src/provider/api_provider/api_provider.dart
index fee552c..cf0c1cf 100644
--- a/lib/src/provider/api_provider/api_provider.dart
+++ b/lib/src/provider/api_provider/api_provider.dart
@@ -78,7 +78,7 @@ class ApiProvider {
             url, json.encode(digestData));
         BlockCypherTransaction? tr;
         if (response["tx"] != null) {
-          tr = BlockCypherTransaction.fromJson(response[["tx"]]);
+          tr = BlockCypherTransaction.fromJson(response["tx"]);
         }
 
         tr ??= BlockCypherTransaction.fromJson(response);
diff --git a/pubspec.yaml b/pubspec.yaml
index db0df13..dadc958 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,6 +1,6 @@
 name: bitcoin_base
 description: A comprehensive Bitcoin library for creating/signing and spending P2PK, P2PKH, P2SH, P2WPKH, P2WSH, Taproot ...
-version: 1.3.0
+version: 1.4.0
 homepage: "https://github.com/mrtnetwork/bitcoin_base"
 repository: "https://github.com/mrtnetwork/bitcoin_base"
 Author: mrhaydari.t@gmail.com