Vivint sent me to collections but I never signed a contract

Location: Pennsylvania, USA

I bought my house in May 2025 and the family that previously owned the house had a Vivint system installed that they were unable to take with them due to moving to an apartment building. When buying the property, the family had an active contract and was supposedly still paying on the equipment. I was doing renovations for a little over a month before completely moving in, so I didn't mind the idea of having some kind of security for the times I would not be at the house and had planned on shopping around for security systems in the future.

I had contacted Vivint and explained the change in ownership of the house, the equipment already existing in the house, that I did NOT want a contract, and that my service with them will be very temporary. All communication I had with them was over the phone. I spoke with two guys that worked for Vivint but were local, presumably the technicians that install the equipment, and they were able to turn service on virtually and never came out to my house. During these phone calls, I reiterated to them that I am not signing up for a contract to which they both confirmed and understood and only charged me the monthly service fee of $41.47 on June 9th.

I received an email welcoming them to their system and that I had a 24 month contract. I never signed a physical or electronic contract, but of course, Vivint is claiming I did in fact sign a contract. When I call and demand they email me a copy of the contract I supposedly signed, they give me the run around, say that they will email it but, shocker, never send anything. The mail I receive from Vivint spells my name very wrong; how could I have possibly signed up for a contract misspelling my name? I followed the cancellation procedures that Vivint customer service gave me and emailed my notice of cancellation on August 7th with all the information provided. I also asked for instructions on how to send the equipment back and was told that the equipment is paid off and too old for them to want back anyway. They continued to charge me for 3 months and after getting nowhere with their customer support, I just cancelled my card and ignored their phone calls and emails about missed payments.

Fast forward to a couple weeks ago, I received an email and letter in the mail from a collections agency called Sequium in the amount of $547.15 of missed payments and late fees. I'm worried about this affecting my credit score, but at the same time, I'm not paying that.

Any advice? Now that a collections agency is involved, I'm not sure what rights I have. Should I get a lawyer and argue that I never signed a contract and was falsely told that I would not be signed up for one? How can I get Vivint off my back with minimal damage to both my credit score and my wallet?

Tldr: Vivint sent me to a collections agency, what can I do?