MTN DEBIT - no contract with MTN [#***4]

MTN have been debiting my account for the last 2 months for different amounts , I HAVE NO CONTRACTS AT ALL with MTN yet they still debit my account every month on the 1st .

I have sent an EMAIL TO THE ACCOUNTS ***** department and i have no received feedback. MTN !!!!!!!!!!!!!!!!! PLEASE GET BACK TO ME ASAP WITH A LETTER OF CANCELLATION FOR A DEBIT I DID NOT APPROVE AND A APOLOGY.