The redirect URI in the request, https://www.multiplayertreffpunkt.de/index.php?google-auth/, does not match the ones authorized for the OAuth client. To update the authorized redirect URIs, visit: https://console.developers.google.com/apis/credentials/oauthclient/1082836957963-odrkrt2c5jpb2ttkbrbe7ulv8k0garpg.apps.googleusercontent.com?project=1082836957963