Pathetic service by cell c

I have been trying to upgrade my contract with cell c since early January . It all went wrong when they sent the incorrect phone , and that is where all the drama began . I have made close to 50 phone calls to cell c , have been speaking to supervisors and yet the issue has not been resolved . The supervisors apparently don’t have anyone else that they answer to and refuse to allow u to speak to their superiors . I now have received the correct device however they have decided to bill me an extra R 400 per month and no one willing to answer questions. This morning made two calls , the Second lasting 50 min and cut thereafter and still have not spoken to someone to assist . They haven’t called back either . To be honest they are the worst company I have ever come across ( when u have an isssue to resolve ) ever . I have dealt with government institutions in South Africa that are really really bad but cell c tops the list