Screenshot detection library does not detect screenshots

I want to detect screenshots inside a specific activity inside my app. I decided to use this ScreenShot Detector library but unfortunately this does not detect any screenshots for some reason. I added some code to my activity to check if all the required permissions are grandent and it still doesn't work.

My Activity:

public class UserProfileActivity extends AppCompatActivity implements ScreenshotDetectionDelegate.ScreenshotDetectionListener {
@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_user_profile);

        ActivityResultLauncher<String> requestPermissionLauncher =
                registerForActivityResult(new ActivityResultContracts.RequestPermission(), isGranted -> {
                    if (isGranted) {
                        Toast.makeText(this, "Permission ok", Toast.LENGTH_SHORT).show();
                    } else {
                        Toast.makeText(this, "Permission req", Toast.LENGTH_SHORT).show();
                        // Explain to the user that the feature is unavailable because the
                        // features requires a permission that the user has denied. At the
                        // same time, respect the user's decision. Don't link to system
                        // settings in an effort to convince the user to change their
                        // decision.
                    }
                });


        if (ContextCompat.checkSelfPermission(this, Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_DENIED) {
            // You can use the API that requires the permission.
            requestPermissionLauncher.launch(Manifest.permission.READ_EXTERNAL_STORAGE);
        }

@Override
public void onBackPressed() {
    super.onBackPressed();
    finish();
    CustomIntent.customType(UserProfileActivity.this, "right-to-left");
}

@Override
protected void onStart() {
    super.onStart();
    screenshotDetectionDelegate.startScreenshotDetection();
}

@Override
protected void onStop() {
    super.onStop();
    screenshotDetectionDelegate.stopScreenshotDetection();
}

@Override
protected void onResume() {
    super.onResume();
    screenshotDetectionDelegate.startScreenshotDetection();
}

@Override
public void onScreenCaptured(@NonNull String s) {
    sendNotificationToUser("screenshot");
    Toast.makeText(UserProfileActivity.this, "Profile Screenshotted", Toast.LENGTH_SHORT).show();
}

@Override
public void onScreenCapturedWithDeniedPermission() {
    Toast.makeText(this, "Permission denied", Toast.LENGTH_SHORT).show();
}

}