iCloud for windows/Apple account verification code.

Trying to install iCloud for windows on a Windows 11 Pro laptop using my Apple ID and password. Apple account verification code is sent to all my apple devices and either it quickly disappears before I can tap “Allow” or it lets me tap “Allow”, briefly shows me a code that disappears too fast for me to enter it.

When signing in to this site from my iPad, or indeed from window 11 laptop, it appears on MacBook, iPhone and iPad and allows me to tap “Allow”, access and use the code.

This is a known issue. Why does it keep reappearing?