2000 yucon door lock

I have a 2000 yukon and one of the back door locks will not work.It seem to be stuck and will not open with remote or inside the truck. I took the door panel off and the lock is very tight sprayed with wd-40 no help

Thanks

Did you ever get this resolved? I have a 2000 Tahoe, and the right rear power door lock is doing the same thing. Cannot not move it manually either.

Thanks