Cell C **********ly blacklisting my name.

There is a ********** contract phone on my name dating back to 2021, I went to report it to Cell C same month there was a transaction on my account. They promised to escalate the matter to their ***** department. It was then said that my name was cleared in December 2021. It's been over a year now and I have been receiving calls this week from debt collectors this whole week saying that I owe Cell C, this is frustrating as at the Walmer Park shop I keep on being redirected to their ***** department and I have sent all the necessary documents and affidavit. This is my last resort, please I need all the help with solving this matter and I currently cannot apply for anything as my name is under credit debt review due to this .