MTN cancel my dam contract and stop debiting me for nothing !!!!!!!!!

Absolutely pathetic service from MTN , mangers dont take the calls make you wait so on calls , manager cannot even give me proper feedback , i returned my router to the store and they gave me back the sim card. cancellation was not done by manager and then the store closed down , Manager of store is not taking my calls . The told me only the manager can do the cancellation on Monday as he was not in. Still being debited for something that im not using. Cancel my contract and stop debiting me !