[Koha] errors on opac log

[Paulo Neto]

Hello,

I am getting lots of these errors on opac log -opac-error.log-

[Thu Oct 19 17:24:15.428577 2023] [cgi:error] [pid 19289] [client xxx.xxx.xxx:35920] AH01215: [Thu Oct 19 17:24:15 2023] op
ac-ISBDdetail.pl: Use of uninitialized value $holdingbrtagf in string eq at /usr/share/koha/lib/C4/Biblio.pm line 755.: /us
r/share/koha/opac/cgi-bin/opac/opac-ISBDdetail.pl

How can i solve this ?

Paulo Neto

DGADR
DSIGA / DPGI
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