Misleading sale and wifi speed limit

I year ago I bought an MTN uncapped WiFi of a month to month contract. Everything was well till now in June my speed was reduced down . When I called the technical team on *** to solve my speed issue, I was told I used my 100% limit for the month. The contact is uncapped and was told in the begging that I should use the 100% limit for my speed not to go down . Now that has changed. I spoke to 3 different consultants and they all gave me 3 mtn different numbers to fix my problem with Sales department and found that they are closed on a friday at 16h00. When I ask to speak to a manager I was denied. Does this mean no one can help at MTN?