POOR POOR SERVICE MTN

I am very disappointment with MTN they are the worst when it comes to solving a client problem that the have created internally.Let me explain i have contacted MTN for the last two week as all of a sudden my uncapped LTE line of two years with a speed of 20mb has all of a sudden changed to cap line. I have never called them or gave them permission to change this line. So one of the consultant i spoke to on Monday said that it was change by someone inside MTN on the 17 April without my permission. So for the last two week , I spoken to several of their consultant and they promised it will be solved. I don't understand what is the problem and the problem they created they can not even sole. I really hate MTN at this point . They change my package at this point without my consent and i still pay the same amount for a lower package. They said i will receive and email in 72hour still waiting up till now i have not receive any communication or feedback if i don't call them , yet it will be another dead end conversation.