Refusing to cancel my contract, terrible service

I cancelled my contract on the 19th of September by following the exact requirements. The contract should have been cancelled on the 19th of October when they should have switched my account to prepaid. It was still not cancelled on the 29th of October. When i phoned they said its my fault because they couldnt speak to me on the phone, i was in hospital the day they phoned. I phoned and asked to speak to the cancellations department, they dont take incomming calls. When i phoned the call centre and requested to speak to a manager the call operator put the phone down in my ear. I have 2 other contracts that i am also going to cancel due to absolutely terrible service. I follow the steps from my side and still they do not do their work