Contract cancelled but not done by Cell C -

Cell C offer me a S4 tab more than a year ago, the device did not work, I send it back twice and cancel the contract. Now they charge me for the use of this devise, I phone them and talk to 7 different people and still after an hour no success. Someone in Cell C did not do their job and it is a mission to get this sorted out. <br> <br> I had complain and they contact me, I send all the require documents, and now it is more than 2 weeks and no repose from Cell C, they even deduct another R1005 from my account end July. This is not acceptable.