Stuck in 4WD part time

My 1999 JGC is stuck in 4WD part time, it's a select-trac. Just started doing this without even having it in 4WD. Tried driving in reverse after changing to 2WD, no help. It will shift to neutral and 4WD low, no problem. Any ideas would be appreciated.

make sure you have the transmission in NEUTRAL.

The shift lever moves but it doesn't disengage out of PT 4WD.
If this is the procedure, let me see if i'm doing this correctly.
Selec-trac is currently in 2WD.
1. Put tranny in N
2. Shift Selec-trac into PT 4WD
3. Tranny in R
4. Tranny in N
5. Selec-trac into 2WD
6. Tranny in R
Tranny back to D, should be fine?
Do I have to go back into PT 4WD?

Thanks for the quick reply. :)

I had a similar problem when I was wheeling once, but instead it wouldn't go into 4 low. I later got underneath the jeep and started snooping around and found that the 4wd shifter lever near the diff was loose and had lost one of the bolts. I replaced the lost bolt and tightend the other and it has shifted in and out perfectly since.

I'm not sure if you have the same issue but it's something to look into.
I was also told that tire pressure needs to be the same in all tires or else it sometimes wont shift back and fourth.