Upsetting service

Over the weekend I took out a contract with Mtn at the branch. To my surprise the guy that assistant me advised me that the uncapped WiFi deal I have taken out I am being over paying, hence from Monday I been trying to resolve the matter, with no joy and all my mintues and R110 airtime drained out. I pay R999 for a 50mbs line whereas MTN is offering a 100mbs for that very price, so for the past six months I have paid R1200 on the dea extra, plus the router I received is not the router that comes with the deal. As a loyal MTN customer with a number of contracts. Think it is only fair the deal corrected/ amended and router exchanged. Spoke to a lovely lady at MTN on Monday afternoon whom was willing to assist me but unfortunately our call got cut she agreed to making it right. Would appreciate if someone would sort this matter out asap.