Very bad service

I am fed up with mtn, horrible service been struggling for almost a week and a half with my wifi which i have paid for haven’t received the new months data been buying data just so i can use my router, how can you pay for a service that isn’t even working and i know for a fact that they will bill me at the end of the month for the contract even tho I wasn’t able to use the product that i am paying for, really not happy.