MTN - no response to complaints

I upgraded my cell and they did not apply the discounted rates as promised (listen to voice recordings). When I got my statement and realized the discrepancy I contacted them several times. You wait on average 45 min per call. Got my next statement and it was still not rectified as promised. Ref numbers ***, ***, ***, ***. Sent several emails in an attempt for ownership but to no avail. Keerasha Salikram, Maurisha Olivier, Refiloe MAbanda, Xolile Dlamini, Sancia Meth, Business KZN, Complaints@mtn, KZN Corp Support. But still no confirmation. I find this service totally unacceptable? Why could this not have been done right the first place? I have had to log calls to have the fees reversed and the correct fees app**** and the process is so frustrating! I even asked someone to contact ,e to have my other cell upgraded - they promise to phone me and they just never do!