very bad customer service

I have two contracts with mtn for my phones which have been giving problems since the word go...also it has been replaced before and has been in for repairs about 3 4 times now.1stly the consultants working there have no people's skills they either they either busy their phones when u there or show no interest in your problem.I have sent both phones in once again for repairs which, has been a norm since December and 1 of them have been in 4 more thn a month I have been paying for almost 3 months with now with no phones.the manager said he would assist but up to date still no assistance.I went in on the 13 February 2015 again after I spoke to the managers head and all they could say was the 1 phone has been assessed and will have to be replaced but they don't have stock and don't know when they will have.they also continuously mention they only a franchise and can't do much, my question then why are u there?I have suggested them replacing both my devices with something else but they just seem to not be hearing me because even after I mentioned that they still show no interest in assisting.I am really at a stage where I want to cancel both my contracts.