[Koha] need help in fine calculation

Hi there , i am doing a cataloging system for my library using the koha . As it still new , i rather use KOHA V 2.24 as an introduction of OPAC . However , i get a problem on the fine calculation . I have define the fine in issuing rules . However the charge value do not change even the due date is over for 4 month . What should i do --------------------------------- Looking for earth-friendly autos? Browse Top Cars by "Green Rating" at Yahoo! Autos' Green Center.