Egroupware - Identitäten löschen (deleate identity)

Hi - I’m accessing two account from my account. Both on the same egroupware server. I would like to call one as primary (directly linked with my account and the other the secondary (added later on).
Within the primary I can add and delete different identities. With the secondary I was able to add new once a longer time ago - but than I identified, that I’m unable to delete these identities. I’m getting the following error after selecting the one that I want to delete (just selected):

As you can see - there is as well no option to delete the identity - just the account itself - what I don’t want.
grafik

I can still use these identities when sending mails.

I’m on version:
grafik

I can still add identities - but deleting it right after is not possible.

Any idea who to solve this?

Thank you in advance