mtn HOME WIFI BILLING AND WIFI NOT WORKING

Good day

This is my second complaint with MTN because the first one was never attended to .I receive no response , I have an uncapped HOME WIFI with MTN which I pay R529 . This month I was told to pay almost R300 but I had paid the normal R529 as per the contract . Now the WIFI is off and not working . I'm highly disappointed and did not expect this from MTN nogal .I need my WIFI to work ASAP as I'm working from home .Thanks