[Koha] Call number display in holdings table and

I need the call number field from Marc21 082a displayed in the holdings table in the bibliographic detail of the record in the OPAC. I tried using the value builder cn_browser.pl, but it did nothing. I removed it from the marc framework and now when clicking on the title of a book from the catalog search screen gives this error: "The record you requested does not exist()." However, if I click on the pic of the book cover, the record displays fine. What can I do to fix this and display the call number in that table? Thank you, Andrew Hartung