**** service from Netstar

I have sent 3 emails and numerous phone calls to cancel my contract with Netstar. My car has been sold 4 months ago and this morning (8/7/2025) I get a threatening sms from a collections company to pay my Netstar monthly contract. This contract should have been canceled ages ago. I called to your office and an agent confirmed telephonically last week that it is canceled. I called again this morning 8/7/2025 after receiving this sms just to hear the contract is still active. I am going to the media with this **** service from Netstar. Cancel the contract, what is so difficult about doing that?