An already Fully settled account of 5years ago

I have had two accounts with capitec bank in 2006,when I was unemployed I wasn't able to settle the account,but did so a few years later. But now what's happening is every 2 or 3 years they are HARASSING me for payments that's has already been settled. I have both the account numbers with both reference numbers with receipts shown I have paid, then alls goes quiet until 2 years down the line again. They have phone me on numerous occassions and I told them I have settled these accounts and that they should send me an email address where I can email my proof of payment to them AGAIN after this reoccurence every 2 years,no email was sent as requested,but this sms comes to my phone every 2nd week:The bal on your ASC CAPITEC 3 acc is R 8764.88 call SDK on (0861)111-689 to arrange pmt Ref***.STANDARD BANK *** BRANCH CODE: 051001. This is the contact number they call from every 2nd day:+***. This is unexceptable!!! Its harassment. If this continues I'll have to take further steps, I have told them if they call or sms me once more I will expose them to Hellopeter, still it continues.