Privacy settings in personal information missing in some accounts

I have the issue that for some accounts it is not possible to set the privacy settings under personal information (Private, Trusted or Public).
Because of that, these users are not visible in the contacts shortcut in the title bar.

It seems that when these users were created, some option in the sharing menu was disabled.

Unfortunately it is not possible to edit any user specific settings to sort this out, the only option seems to be to delete the user and recreate it. With many users and data, this is obviously not an option.
Is there any solution to fix this without deleting the users?

Nextcloud version ( 20.0.3):
Operating system and version (Linux 4.4.0):
Apache or nginx version (hosted server
PHP version (eg, 7.4)