How to delete duplicate users in the user list

When I displayed the user list as an administrator user, only two user were duplicated. It’s all the same for usernames, email addresses, groups and more. The same user is shown even if logged in using the NC user impersonation app.

  • This could not be fixed with occ maintenance:repair.
  • This is not duplicated in the occ user:list.
  • There are two differences between the number displayed for all users and the number of users displayed in the list. All users are seeing fewer than they actually are.
  • There are no duplicates in the DB oc_users table.
  • Even if I give administrator authority to another user and the user looks in the user list, the user in question is duplicated.
  • Duplicate users have administrator rights. However, even if I give administrator rights to other users, the users are not duplicated. Duplicate users have administrator rights from NC12.
  • Even if the authority is removed from the second administrator, it is displayed twice.

How can I fix this?

Nextcloud 17.0.1, CentOS 7.7, MariaDB 10.2.29, PHP 7.3.12, Nginx 1.16.2

Why the user is showing again and again?

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