[Koha] Error upgrading to 21.11.

Upgrading from 21.06 the webinstaller stops with: Upgrade to 21.06.00.012 [15:11:07]: Bug 15067 - Add missing languages ERROR: {UNKNOWN}: DBI Exception: DBD::mysql::db do failed: Duplicate entry 'IN-region' for key 'uniq_lang' at /usr/share/koha/lib/C4/Installer.pm line 738 What can I do? Beda