Seller sold me a Blacklisted phone, what can I do?

I bought an iPhone XR at a store may Be about 6 months ago. I should've been on alert when the seller was saying the phone was unlocked, but not to reset the phone. Anyways I moved from att to Metro PCS and while trying to get the SIM card to work, they said that the phone was blacklisted. Which is weird because att took the phone and I was able to use their services. What can I do? Go back to the store? I know that Indian guy will try his best not to return it, especially after 6 months.

Added (1). Should I call the police as well? Onsite if he doesn't want to do anything?

You bought a lost or stolen phone.

Give it back to him and ask him for your money back

Only deal with reputable stores. You thought you got a bargain. They fooled you with a lost or stolen phone. There's no way you will get the money back, at this point. The police will NOT get involved in this, as it is a civil matter. You could try filing a claim in small claims court, if you can prove the phone is lost or stolen.

6 months ago? You are likely out of luck. What do you think the police are going to do?

Here's the deal, you have no way to prove that the phone you have had for 6 months is the same phone you bought from the seller. So police are not going to do anything. The court won't be much help to you either. So take this as a lesson learned and pay attention and ask questions next time when buying a refurbished phone from Apple or a carrier. No more ads for you.

Do? Do as you wish.

You should not have bought blacklisted phone. Try to give him back at little discount.