Poor customer service

I took a cellphone contract with cell c but only received a sim card, after calling and sending emails without any luck a finally got hold of the sales agent who helped me with the initial contract agreement by the name of funeka but she hung up on me and After months of trying to cancel the contract without any luck a received a phone with another sim card but now they're telling me that l have to pay more than the initial agreement. By the way, I still want to cancel my contract