Supersonic very poor service!

I am so disappointed in their service! I cancelled my contract in Nov 2025 with the cancellations department. Dec was my notice period. I now received an SMS from a Debitors company stating I have been handed over to them from Supersonic. They charged me for Jan and Feb 2026. I have been phoning sending emails and still this has not been resolved. No one is responding to my emails and I keep sending them the proof of cancellation. I have tenants in my house who signed up with them so how do they charge both of us for the same address? Supersonic I will never make use of you or promote you again! Until now I am just receiving messages from the Debit collectors and that is it!!!!