Proof of Forged Signature

Location: Warren, MI

Salesman for ADT/Safestreets did docusign on a 3-year contract, in my name without my knowledge. Put in my name and info so it looks like I signed but it is just digital initials and digital signature. Safestreets is ignoring all written contact through email, absolutely refusing to do anything and lying about doing a fraud case. Their only proof is it has my name on it..
They even threatened that they could look at IP address to which pissed me off for the “threat” but would honestly work in my favor since it was on the salesman’s personal phone.
I thought about that and then did my own research and found on the actual Docusign, there is two different IP addresses. One from the salesman’s phone, and one from mine from when I first viewed it. I was only sent a copy of this contract to my email AFTER he signed it. It was never formally sent to my email for ME to sign.
I have sent them the proof and have had multiple missed calls from them. They continue to fight this and say the contract is still valid.
I even asked the salesman if there was any contracts or how to cancel, as I just told him the story of how I left another company because I did not want to be locked in. “Oh, nobody ever cancels.”
I did not want this. Everything about this was shady. Sales guy even made us give him money and a drink for tip..I believe the forged signature happened while I was in the kitchen..I know I should’ve just turned him away in the first place, I did interrogate him but I was lied to anyways.
What else can I do? How do I get them to cancel the contract without penalties since I never agreed or signed to this?