Problem deleting user accounts from Admin Panel or CLI

I'm having trouble deleting user accounts from the Admin Panel or CLI.
When trying to delete an account from the Admin Panel it simply doesn't delete or do anything, the window just freezes. The rest of the functions such as closing the account work without any problem.
When trying to delete the account from CLI using:

carbonio prov da user@mydomain.com

it shows me the following error.

ERROR: service.FAILURE (system failure: Delete account user@mydomain.com has an error: Failed to publish delete user requested event)

The services are running without problems and the server works just as well without any issues.