I am encountering the following problem since a few weeks now.
When I post a message within a Teams chat and I want to delete it, I see the menu entry 'delete' ('löschen' on German) but when I click it, I receive a 'Fehler beim Löschen' ('error during deletion') message.
This happens on Teams for Mac Version 1.3.00.24758 but also on Teams on iOS13.7
What is strange, is, that it worked all the time but only recently started to fail on nearly every incident. Also I've observed that for the fraction of a second there appears a confirmation that the message has been deleted before the error message is displayed.