Hello Ralph, and welcome to the community!
Most likely related to this issue with iOS, with a work around:
https://old.reddit.com/r/Bitwarden/comments/1de388c/ios_can_no_longer_log_into_eu/
as a workaround, please enter vault.bitwarden.eu in the self-host flow: Connect Clients to your Instance | Bitwarden Help Center
Github issue, already closed: