cell c breach their side of contract

Last year about june i contact cell c to complain about my cell phone reception. Around and in my house me and my wife ( also cell c ) could not use our phones. I went as far as bought another phone but stll the problem presist. I contact cell c and they send their people out to check the signal. they find i had no signal by me. They told me they will cancel my contract. I went to vodacom and cell c let them transfer my no. In august 2014 cell c phone me and say they want to pick up my phone. They never come. Since then they keep on deducting our monthly payments. I phone them few times but they just keep on. Me and my wife went to the bank and stop it but they change the debit order no every time. Every time it cost us bank fees. I then went to legalwise and ask them to deal with them as a sane person cant. After about 7 months i got a letter from legalwise to confirm the matter is resolved. legalwise send me copies of all correspondence between them. my legalwise ref no is KN/***VNG. And you wont believe it they still try every month to deducted money from us. Now they even phone me to ask why my acc is not paid. can you pls help me with this matter. Thanks