IPhone XS on sprint?

I have a iPhone XS through sprint and I had not been fully paid off (long story) anyway they **** the service off.
Is there anyway to unlock it from sprint to use on att prepaid or something of the sort? I read somthing online about the special SIM cards? Do these really work?

Apple have been cracking down on those SIMs, recently they changed a bunch of codes that stopped them from working.

The only way you can get this to work is if Sprint will allow you to pay off the rest of the phone. If not then you're out of luck

Until that phone is paid off in full, it will be blacklisted from being activated on Any carrier in North America, Europe and most of the rest of the world as well. So no matter the "long story" or who's fault it is, you are stuck paying the phone off before you can use it on any carrier.

Nope. You pretty much have a stolen phone (it isn't yours until you pay it off). Sprint will not unlock the phone nor will it be easy to get it unlocked. I tried using an RSIM on a TotalWireless iPhone 6 and it doesn't work correctly. So until you pay off what you owe to Sprint, you won't be able to unlock your phone.

It's very difficulty.