[Koha] A question about Issuing rules

Hi! Working with Koha version 2.2 we find the following problem: Our University has 2 library branches, as each one has different issuing rules we completed the boxes for each branch in the parameters section. However, when we are borrowing, the system automatically sets the due date the same day we borrow the material. Aparently, the system is not considering the issuing rules we had defiened. Can anybody give us an idea of what are we doing wrong? Thanks in advance, Laura Ferreyra Universidad ORT Uruguay