Help with Sprint service?

So I switched to sprint and 2 days later I switched to Verizon. I traded in my iPhone7 for the XR at the sprint store. I would either like the iPhone7 back or a refund for it. Sprint customer service is telling me they can't provide the iPhone7 back and the store is saying they can't guarantee a refund. I want something back somehow. What can be done?!

Pretty sure you will not get that phone back and you probably just owe the full amount now on the XR.

I don't get it, why should you get a refund? Better yet… How do you plan to spend that $80 credit they'll give you for it?

It doesn't matter "what I want".
Does the Sprint contract allow you to cancel? If so are there fees to cancel?

Also, your phone is gone.
You purchased the XR. If you haven't paid for that in full, you still owe the remaining balance on it.

Hopefully you didn't pay cash. There's no way they can keep your money AND the phone. If you put it on the credit card, dispute the charge and let them know that you're doing that if you don't refund the phone or your money back. Then do it.