New service started on my old account, but not from me!

Hello, I want to follow up on a problem ticket (# [Edited: "Personal Information"]) which I thought was resolved with Xfinity and the collections agency.  However, a new collections agency has contacted me recently regarding this.

Moved out of my old apartment and transferred services to my new house on 9/6/2023.  I was given a new account number and paid the transfer fees for the new internet service.

In August of 2024, I cancelled my internet service altogether.

In March of 2025, I get a notice that I'm late on my internet service payments and that my bill would be sent to collections... and a few weeks later collections started calling me. 

Thinking it might be a scam because I had disconnected my service and the account number from the collections agency did not match my account number... So I did a live chat with Xfinity.

The rep tells me that after I cancelled my service, a new service had started at MY OLD APARTMENT.  He tells me that equipment had been sent there and service was still pending activation.

I explained that I had moved out of that apartment almost (at that point) 2 years ago.  I cancelled the service at my house in August of 2024 and NEVER activated a new service anywhere.

I worked things out with the rep, and he gave me the above reference number.

I gave this reference number to the first collections agency back in June 2025, never heard a thing after that until a new collections agency sent me a notice for the same account.

I'm confused as to what to do at this point.  And have a few questions:

If Xfinity believed it was a transfer (or new activation) back to the old apartment, why was the old account number being used?

Also, was there ever a new activation or transfer fee charged?  I had already taken my credit card off the site before this point, so curious how this transaction was completed.

That's why I think there's some type of glitch.  But I want to follow up to see if this issue is still with Xfinity (which I thought was resolved) or just with collections.

Thank you.