[Koha] koha controll number

Hello, we have a problem after upgrading to Koha 21.05. When you create a new record it was earlier that you have to go to this url: https://hostname-intra.domain.com/cgi-bin/koha/catalogue/detail.pl?biblionum... edit, edit record https://hostname-intra.domain.com/cgi-bin/koha/cataloguing/addbiblio.pl?bibl... under 001 you get a continuous control number with the name of the university at the beginning. Since the update there is a different number for new records, which differs from the old scheme. It starts completely different. Where can I adjust this again?