POOR SERVICE

I have a complain that has been neglected by MTN SP since feb2022. I had contract on ****** that ended and cancelled in jan2022. I was put on zero rated plan, receiving no bundles from MTN SP. since February 2022 MTN has been Billing me approximately R1100. I called and was given many references and I was told my query will be escalated to date nothing happened. This has affected my credit report very negative as it reflects a huge amount of outstanding amount that I don't even owe. It's over a year calling for same thing. MTN complaint department failed to assist me.