USELESS !!!

i had a previous complaint with telkom where i was liable to pay an incorrect amount on a cancelled account, ref no SM92770, this has since been sorted,however Telkom Mobile has now sent my details to NUDEBT who are HARRASING ME OVER THE PHONE DEMANDING THE MONEY i already paid to telkom.the team leader i have been dealing with does not even have the decency to give me a call to have this sorted instead they insist i still owe money to telkom.My mails to NUDEBT are not being answered and no one can is taking this serious..... very disgusted with how NUDEBT is treating me !!!