CONTRACT EXPIRED BUT MTN CONNTINUE TO BILL AND OVE

On 08 May 2015,i contacted MTN call centre to inform of my intent to cancel contract with effective form 30 May 2015 and I was given reference number. Subsequently I wrote email same day to request confirmation in writing using reference number given to me i.e ***.Then on 17 June 2015 I receive an email form MTN requesting me o sign cancellation form of which I did and I even inform them that the 21 days required wont apply form the date of the email as they are the one who delayed to respond to my email.<br> <br> Since then, I have receive numerous call form different MTN department and every time I provide them with proof that my contract was cancelled in time ,they don't come back then I will be called by different person form different department up until recently I was informed that MTN has flagged me as a bad customer.<br> <br>