Bad service sanlam Sky.

I have 3 policies with Sanlam Sky. Ive had these policies for the past 10 odd years with no issues. About 8 months ago I changed jobs and changed debit order dates. I called Sanlam Sky to inform them of my new debit order dates but for the past 8 months they have been debiting my account on my previous debit order dates despite various calls to inform them of this. I have had to deal with bank charges month after month despite my engagements with them.