No feedback, calls not answered

We drove all the way from Richards Bay to Gateway in order to have our screen replaced on our S4. Upon arriving at the MTN franchised branch(and waiting forever), we were told they don't deal with that we need to go to the non franchised branch, when arriving at the Non franchised branch we were told that Nashua Mobile did not carry the warrantee requests over to MTN. I can clearly recall that we received communication prior to migrating to MTN (due to closure of Nashua Mobile) that the entire contract would be honoured by MTN. Well, it just seems that no one at MTN is willing to answer any of their phones to clear this up with us. I tried the MTN franchise at Gateway, I tried MTN at Gateway, I tried 808... to no avail. It just rings and rings and the 808 number, well, what a waste of time. What is going on MTN? What is the issue with old Nashua Mobile or rather New MTN Clients? Are we not valuable enough? Who are we supposed to contact to have this sorted?!