Problems with Bondtouch account registration

I’ve installed iodé on a Pixel 7a for my brother and he wanted to install the Bondtouch App on it. While this was fine and the app was able to connect to the bracelet it was not possible to login to the account. Typically a SMS is send to the phone but on iodé a Captcha is shown. After solving it correctly just the message “Something went wrong” appears.

Does someone has also Bondtouch and experienced the same issue?