TERRIBLE QUALITY DEVICES WHAT ARE WE PAYING FOR ?

Tell me why I pay R240 a month only to have to pay extra when YOUR device suddenly gets faulty and stops working? I have been requesting to cancel this contract from July 27th with no sucess. I sent emails to your agents Gail Misengi and Reitumetse Phuthi and nobody got back to me now I am being expected to make payments for the past 2 months when I specifically requested to cancel the contract