Hello S. Knop
Welcome to Microsoft Q&A Platform, thanks for posting your query here.
There was some intermittent issue with the service as mentioned in this thread.
https://learn.microsoft.com/en-us/answers/questions/1652291/next-steps-user-stuck-in-deleting-mode
The issue is fixed now as confirmed in the above thread.
Can you please refresh and check once.
Hope this helps.