1999 GMC Yukon stuck in low gear

The trailer hitch was rusted in so I hooked it to a large oak tree with a chain. I put it into low-low gear and gently tugged it and it came out with no problem. Now, I can’t get it out of low gear.

Sounds like a problem with the transfer case, maybe the transmission.

I’d have it towed to a transmission shop, myself.

Manual transfer case or push button?

If you put the transmission in neutral can you get the truck back in high range?