Breach of contract

On 30/04/18 i renewed my contract with you. I was supposed to get R120 airtime a month, paid the admin fees of R150. I can't phone out and nobody can phone me. I've been to the Vodacom shop on the Bluff in Durban 3 times since then & they say they can't do anything about it. They reported the problem and said JHB never game them an answer. I'm very upset!!!! I told them to cancel the contract but they wouldn't, i tried giving the phone back but they not interested. I don't know what to do as i'm paying R230 a month for nothing. Absolutely disgusting service! Got a phone call from Vodacom saying that it will be sorted and an email saying I am forwarded to back office. To date I have not heard back from anyone. Getting really fed up now and wish i could just cancel the contract! Looks like i've got a fight on my hands!!!!!!!