Issue with level streaming

I have it set up just like in one of the youtube videos I saw but as soon as I unload the previous level. (I have it set to unload the second I step out of the trigger box.) My character immediately freezes and I have no input at all. How do I fix this. I have the persistent level set up as the current one, this hallway I’m trying to load in the load level stream, and a mansion I’m trying to unload. But then that is where I’m losing control. I’m trying to go for a looping effect of the same level but with a few things changed when the new level appears.