Beyond Frustrated

I cancelled my service last year August for my house. I have moved back to this house and my service provider has said supersonic still has the line and did not cancel it. Therefore they can not assist as I need the line from Supersonic. I logged a request to activate my WiFi and they did so then I log a call for cords to be replaced and the agent has not gotten back to me I had to go to the fibre company myself. I called multiple times and they tell me the ticket is sitting with someone who they do not have contact details for and cannot put me through to them. I then speak to someone else and they tell me I need my router replaced. No-one calls me back or assists and I have to call them to get any assistance. Which is still not helping. It’s been over two weeks that this is persisting and Supersonic does not care. How can this company be allowed to operate like this?