Build failed with an exception using flutter flavors - flutter

Question

When I use the Flutter flavor the app gets an error
My app/build.gradle
android {
compileSdkVersion flutter.compileSdkVersion
ndkVersion flutter.ndkVersion
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
kotlinOptions {
jvmTarget = '1.8'
}
sourceSets {
main.java.srcDirs += 'src/main/kotlin'
}
defaultConfig {
// TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
applicationId "com.example.insurance_admin"
// You can update the following values to match your application needs.
// For more information, see: https://docs.flutter.dev/deployment/android#reviewing-the-build-configuration.
minSdkVersion flutter.minSdkVersion
targetSdkVersion flutter.targetSdkVersion
versionCode flutterVersionCode.toInteger()
versionName flutterVersionName
}
buildTypes {
release {
// TODO: Add your own signing config for the release build.
// Signing with the debug keys for now, so `flutter run --release` works.
signingConfig signingConfigs.debug
}
}
flavorDimension "flavor"
productFlavors{
prod{
dimension "flavor"
resValue "string","app_name","Admin Prod"
applicationIdSuffix ""
}
qa{
dimension "flavor"
resValue "string","app_name","Admin QA"
applicationIdSuffix "-qa"
}
dev{
dimension "flavor"
resValue "string","app_name","Admin Dev"
applicationIdSuffix "-dev"
}
}
}
error throw in line 28
I Have already used Flutter doctor, it perfectly works on google chrome but it doesn't support mobile and emulator
attach my errors
I don't use any other firebase JSON files
attach my project folder