Transfer case issue

Hey guys, I'm new to the forum and was hoping someone can help me out. I have a 1998 4Runner limited with the v6. My issue is last night driving home from work my transfer case went into neutral and now it will not engage back into 4 high. When I put the truck into nuetral to shift back into 4high it will either grind or it will go in. But when it does slip back in as soon as I put it in drive or reverse the transfer pops back into neutral. I had to get towed home and still can't figure out how to fix it. Thank you all for the help in advance. I'll try to post a video of what happens as it may be easier to understand what I mean