RAIN is the worst

Rain want me to pay for something i didn't use. I previously called rain to cancel my subscription because i couldn't afford to pay anymore. Everything was fine and they even collected their router. Recently i receive a call saying i owe the 1200 with means its subscription for two months. But wen i cancelled no one said anything about me owing them. i even checked i didn't owe then anything since its a prepaid . now im receiving an invoice of R1200 that i dont know off. I am not going to pay for it. Rain is a **** .i will never even refer anyone to them. you **** people . Even if i wanted to go back to it i will not. you make people to pay for things that didn't use. what am i wing cause immediately after i cancelled it was collected .you didn't even wait time . Actually you owe me for the days i never used it and already paid for it.