CretaサポートThe app says it is under maintenance
まだ日本語では提供されていないため、原文で表示しています。上のメニューから翻訳できます。
Then it is — that notice is put up deliberately while work is done, and it usually says when service is expected back. Nothing is wrong with your account or your installation, and reinstalling will not help.
Games already installed on your machine are unaffected by platform maintenance unless the game itself needs to reach the network to start.