One of the causes may occur this error may be the mismatch between Gradle version and Android SDK version. I suggest these steps to make sure, we are using right version of Gradle.

1. Open the "android" folder inside your Flutter project with Android Studio: make sure to open just the "android" folder not the whole Flutter project with Android Studio.
2. Wait until Android studio automatically download and install the Gradle
3. If the Gradle version which Android Studio was installed is not compatible with your Android SDK version, you can find the specific error in the build section on the bottom of the Android Studio IDE.

After downloading and installing Gradle, the error may be gone but if you get the incompatible error, you can follow the recommendations which will be shown on the build section.