mtn is a bad server provider

Account Z*** Uncapped data bundle *** this belongs to a company This morning we could not receive or send emails nor can we open any other websites A page open with the note: you're out of data!!! How can that be? It is uncapped! When calling and after long ads and numerous prompts we were told by a voice that you should call from the number you are requiring about How MTN HOW? It is a data bundle?