OC\User\NoUserException: Backends provided no user object

I see errors in my logs related to a deleted user.
The errors are:
[core] Error: Error while running background job (class: OCA\DuplicateFinder\BackgroundJob\CleanUpDB, arguments: )

And always connected to the following:
Backends provided no user object for <user_name>

The userName is a long time ago deleted user.
I checked and is nowhere to be found. Also I cant find any share on it anymore.
I chccked the for users also using the occ command: sudo -u www-data php occ user:list and is not listed.

Any help is welcome.

NC details

Nextcloud version
Operating system and version Raspberry pi 4B 8GB