Getting harrased by debt collectors

I had 3 accounts with standard bank which were paid off via debt review, i received the paid up letters from standard bank regarding all my accounts, yet i still get phone calls from debt collectors regarding my accounts, i have contacted standard bank numerous times regarding this as well as sent my paid up letters to the bank and debt collectors, every month its someone new calling me, im sick and tired of having to send these documents each time someone calls!!! UPDATE YOUR SYSTEMS! also i have a bad credit rating with transunion because according to standard bank i have been missing payments. you guys are pathetic when it comes to keeping your records up to date and now i am paying for your ****!!!