Hi Our library is working with Debian GNU/Linux 10 and Koha 21.05.05. Since the update the check out process does no more respect the circulation conditons regarding the due date (the loan period is 1643 days) but instead sets the due date to the current date! So If I check out a book today the due date is today. In logfile "intranet-error.log" the following is reported: [Mon Dec 06 12:04:52.123486 2021] [cgi:error] [pid 21882] [client 134.130.93.46:38068] AH01215: Argument "" isn't numeric in addition (+) at /usr/lib/x86_64-linux-gnu/perl5/5.28/DateTime/Duration.pm line 70.: /usr/share/koha/intranet/cgi-bin/circ/circulation.pl, referer: http://79.143.185.37:18080/cgi-bin/koha/circ/circulation.pl [Mon Dec 06 12:04:52.196908 2021] [cgi:error] [pid 21882] [client 134.130.93.46:38068] AH01215: Argument "" isn't numeric in addition (+) at /usr/lib/x86_64-linux-gnu/perl5/5.28/DateTime/Duration.pm line 70.: /usr/share/koha/intranet/cgi-bin/circ/circulation.pl, referer: http://79.143.185.37:18080/cgi-bin/koha/circ/circulation.pl There are no errors in Koha menu "About Koha > System information". Is this a bug that I should report? Best wishes: Michael -- Geschäftsführer · Diplombibliothekar BBS, Informatiker eidg. Fachausweis Admin Kuhn GmbH · Pappelstrasse 20 · 4123 Allschwil · Schweiz T 0041 (0)61 261 55 61 · E mik@adminkuhn.ch · W www.adminkuhn.ch