Harassment without reason

The debt collectors in SA are ********. They harass without reason and charge you for the benefit. RCS had 2 accounts settled. One with Edgars more than a year ago and another Game several months ago. I had to open a case against them with the Ombudsman as they couldn't sort the account out and did not deduct payments made. I settled as soon as this was sorted. Months later I am now getting non stop daily harrassment calls. 6 yesterday on a public holiday. Even though I have settled and confirmed in writing, I am sure they will find reason to invoice