To identify why a fine wasn't applied to a transaction, identify the Patron type, Material format, Holding location and Shelving location. Those four factors come together in the Loan Policy Map to give you the loan policy that would have been applied.
If you open that Loan policy in the Service Configuration > WMS Circulation > Loans > Loan Policy tab, check the following settings:
1. Is the Overdue Periodic Bill field filled in? If not, daily fines will not be applied.
2. Was an Overdue Grace period in effect?
3. Is the Accrue bills when Closed drop-down set to No? This usually explains fines not applied for time when the library is closed, such as around holidays and weekends.
4. Is the user's Patron type one that has fees applied? We often get cases where the user's patron type turns out to be Faculty/staff and the loan policy applied is set to not charge fines.
5. Did the user's account expire before the fine/long overdue fine was applied?
If none of these issues apply to your transactions, please contact OCLC Support.
You can find more information about working with fines and bills here: Manage patron bills