Netstar Contract Service is SHOCKING

Netstar have been terrible! I discovered that I had a 36 month contract with them after selling my vehicle. I don't remember signing any contract, as far as i was aware it was a month to month contract as we have been a client of theirs for years. They cannot provide me with a signed contract. I get told they will call me back and no one does. This has been going on for a month and there is still no resolution in sight. I spent 45 minutes holding on the line to speak to a manager as they were apparently all in a meeting, I couldn't wait any longer and had to eventually end the call. All i'm asking for is proof that i signed a 36 month contract with them, that cant be that difficult to get hold of if in fact its true. Im hoping someone at Netstar will see this and respond to it ASAP, this is beyond ridiculous.