cancelation of contract

i have been trying to cancell my contract with MTN for the whole calling n being transferred to another department that never picks up the call literally hold for hours with no response... my account is settled and i need to cancel it before the next billing which will be done on the 13.08.2021.

feeling very frustrated with this company i want my account to be ASAP can someone please help me i cnt be billed for nonsense n ur incompetence please tu... Even tried going to the store n was advised to call