Account cancellation

My account ended last year Aug 2022 however MTN kept deducting from my bank account, I notified them and cancellation was confirmed by Mtn however a year later I find out through credit check because of a possible job opportunity that my credit check came out unclear due to the MTN account that has been handed over. This is affecting my job opportunity as my credit rating is still reflecting as unclear even though Mtn confirmed I owe R0.00