Bad service

BAD service from MTN

I have been battling with MTN for quite sometime asking them why I am not receiving calls on my phone, NO could advise me until one on Friday of the consultants advised me that my phone was mute from their side because I am using IPhone (what a lame excuses, how can service provider mute your phone without your concerns is that even legal or should consult with the legal team for advise, cause what if missed a very important calls) .