This error message means that Gradle is unable to locate the required version of the 'com.android.tools.build:gradle' dependency with the version number '7.1.1'. This can happen due to various reasons such as:
- The specified dependency version is incorrect or outdated.
- The Gradle cache is corrupt or outdated.
- The internet connection is not available or slow.
To resolve this error, you can try the following solutions:
- Check the correct version number of the dependency and update it in the Gradle script.
- Invalidate the Gradle cache and restart Android Studio.
- Ensure that the internet connection is stable and re-sync the Gradle project by clicking on the 'Sync Project with Gradle Files' button.