Cancel airtime contract

a lady called a couple of months ago offering me airtime for R150 every month which i had to pay R150 monthly,when i asked her if i can cancel this contract anytime i wanted to and she said yes,last month i told them to cancel this contract and its not canceled as yet and they suspended my line my phone its not a contract phone you dont have the right to suspend my phone as if i owe you i was stranded on the freeway friday night with my baby i couldn't make out going calls because of vodacom i want my line reinstated and that stupid contract of yours cancelled its not doing me any justice ill buy my own airtime