Frustrated with OldMutualSA

Worst service and the most unprofessional financial service provider. I have been paying my old mutual funeral policy for over ten years and they keep insisting that I owe them whilst debit orders are going off my account monthly without fail. Also have written confirmation from thier Complaints dept that my policy is update to date however thier call centre disagrees. Branches can't even assist , they also don't get feedback from head office. What the f***k?