Supersonic not so super in Sophiatown

I'm ever sorry that I canceled with my previous provider, although they were not good, Supersonic is way worse. Took a package that is supposed to drop to 10MBs after a certain fup, most days I don't even get close to achieving 10MBs. Support is almost non existent and never able to sort out the issue. My area does not have fibre so limited to using fixed LTE. I'm not impressed. Then I got an invoice dated 16 October 2024 for an amount, no explanation what it is supposed to be for as my monthly subscription is paid but they say my account is in arrears? I paid for the router upfront with the first months subscription so there should not be any other fees. Logged a call, waiting for a response. I wouldn't recommend Supersonic as an option in my area, they can't seem to get the issues sorted. I am looking for another provider and can't wait for fibre to be installed but what to do in the interim?