HOW DIFFICULT IS IT TO CANCEL CONTRACT???

I have tried to cancel my contract multiple times - they I get a statement I am in arrears and must pay after I cancelled it. I pay Vodacom tells me it will be cancelled this morning yet again I get another statement! All I want is for this to be cancelled this sim card doesn't work I don't have it anymore.

I will not pay 1c more. CANCEL THE CONTRACT HOW DIFFICULT IS THIS????????

DONT CALL ME IM NOT INTERESTED IN ALL THE EXCUSED JUST CANCEL THE CONTRACT