[Koha] Duplicate entry 'ar' for key 'PRIMARY'

[Victor Barroso Oliveira]

Hello,
Has any colleague in the group already had this problem when trying to
update the database?

Upgrade to 21.12.00.013  [19:25:20]: Bug 29605 - Resync DB structure for
existing installations
ERROR - {UNKNOWN}: DBI Exception: DBD::mysql::db do failed: Duplicate entry
'ar' for key 'PRIMARY' at /usr/share/koha/lib/C4/Installer.pm line 739

Grateful if you can share with me the solution of the error.