Mont. Code Ann. § 71-1-212

After the full performance of the conditions of a mortgage and whether before or after a breach of the mortgage, a mortgagee or the personal representative or assignee of the mortgagee who refuses or neglects to execute, acknowledge, and deliver to the mortgagor a certificate of discharge or release of the mortgage within 90 days after a request for one is liable to the mortgagor or the mortgagor's heirs or assigns in the sum of $500 and all actual damages resulting from the neglect or refusal.