Disappointing serve

I recently notice that I was being overly charged for data that I didn’t even use, and my router is not working due to the WI FI been blocked but I must pay and to my understanding I should only pay for a service that is being rendered to me. I believe that you are not in a business to ****** people off they hard earn money. On the 01/09/2023 the bill was R780 which was shocking because I only pay R515.00 very month, it later changed to the original amount which I know of R515.00 ,so if I pay that 780 It would have been a loss to me which is unfair. I haven’t used rain since last year September and it’s surprising how the bill keeps on increasing