Supersonic worst service provider ever

Worst customer care ever. After 2 months of failing to uphold their part of their own contract by not installing fiber internet equipment and not supply a service I decided to cancel my application and go with another service provider. Then Supersonic have the audacity to try and charge me for services they have not supp**** which they admitted was a mistake in writing, then out of the blue they try to charge me again tripple the first amount. I have had it with them.