diff --git a/BT901/build.gradle b/BT901/build.gradle
index 2fbd721..478090f 100644
--- a/BT901/build.gradle
+++ b/BT901/build.gradle
@@ -7,7 +7,7 @@ android {
     defaultConfig {
         minSdkVersion 18
         targetSdkVersion 31
-        resConfigs "en"
+        resConfigs 'en'
     }
 
     buildTypes {
diff --git a/Main/build.gradle b/Main/build.gradle
index c932632..f28b7e2 100644
--- a/Main/build.gradle
+++ b/Main/build.gradle
@@ -25,7 +25,7 @@ android {
         targetSdkVersion 31
         versionCode 1
         versionName "1.0"
-        resConfigs "en"
+        resConfigs 'en'
 
         testInstrumentationRunner 'androidx.test.runner.AndroidJUnitRunner'
     }
diff --git a/Util/build.gradle b/Util/build.gradle
index 53202ef..cafa6d4 100644
--- a/Util/build.gradle
+++ b/Util/build.gradle
@@ -7,7 +7,7 @@ android {
     defaultConfig {
         minSdkVersion 18
         targetSdkVersion 31
-        resConfigs "en"
+        resConfigs 'en'
     }
 
     buildTypes {
diff --git a/build.gradle b/build.gradle
index b74df47..f73e84e 100644
--- a/build.gradle
+++ b/build.gradle
@@ -6,7 +6,7 @@ buildscript {
         google()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:7.0.0'
+        classpath 'com.android.tools.build:gradle:7.1.1'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index fc148bc..8d00a91 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-7.0.2-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.2-all.zip