Mobiles Plus representing MTN

I was called on the 22 November 2018 by a company called Mobiles Plus who advised they calling on behalf of MTN. They had info about me and my contract which could have only been received from MTN. They called to sell me a black friday upgrade on behalf of MTN given I was on a black friday promo and was now due for an upgrade. I proceeded to upgrade both my contracts to the new black friday promo which gives you 50gigs of data per month for the 24mth period. After many calls back and forth with Mobiles Plus, they eventually delivered the one contracts phone around mid December and advised they do not have stock of the other phone and will deliver that in the new year. To date I have not received the phone for the second upgrade I did and more importantly I have not received the 50gigs data on the new upgrade I did for which they delivered the phone. I purposely am complaining to MTN because they purport to represent MTN and this terrible service is unacceptable. I have been a client of MTN for 20years and this is unacceptable