Bad Service and attitude

I have upgraded my contract and also took out a new contract. Since the 14th of March we had trouble receiving the new upgraded Samsung A5 phones. First they send me the upgrade phone but the incorrect A3 phone. I needed to courier it back. No one ever phoned back to say they received the phone. Firstly spoke to Siyanda in Deliveries. He had 'n bad attitude telling me that I made the mistake. Not my problem that they did not send the wrong phone. Then I phoned them on Friday , they could not even see the phone upgrade or new phone on the system. They send me a reference number but still no one phoned me today. I then phoned cell c again today and once again got a bad attitude and the phone put down in my ear 3 times. I cannot deal with this anymore. I will rather then move to another provider and they can cancel my contract and new contract I took out.