[Koha] koha controll number

[tuxflow.de]

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?biblionumber=50672

edit, edit record

https://hostname-intra.domain.com/cgi-bin/koha/cataloguing/addbiblio.pl?biblionumber=50672

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?