Infinite loading when joining JIRA via iOS Cloud app

[Marvin Erkes]

When logging in the the JIRA Cloud app on iOS, it stucks in an infinite load on the joining page.

After some time it says that the login failed without any additional information.

• I tried to log out in Safari
• I've reinstalled the app several times.
• Device: iOS 14.2 iPhone XS Max

I'll be grateful for any help.