Unwanted Subscription Ads and Content

I am constantly receiving pop up ads on my phone for mtn play as well as receiving sms's that I am subscribed to services that I have not requested. When I call them I am told it is my fault as I am not being careful about what sites I visit. I have no use for subscriptions that I am seeing! When speaking to the call center and they are clearly unable to assist They REFUSE POINT BLANK to put me through to a manager as they are constantly either in meetings or not in the office. Not one person can assist me in getting these ads blocked that randomly pop up on my home screen. Simply trying to log into my phone and they appear, I am not even on any web browser! This is simply a **** being run by a large corporation and leaving the "little guy" with no recourse against them.