Multifloor elevator crashes game.

I made my first multifloor elevator by following this and for some reason the elevator will crash the game when pressing the button to go from the 4th floor down to a floor under it, its fine the first time but it can’t go from 4th to below a second time. If I press the 4th floor down to the 3rd floor it will go to the second back up to the 3rd, this is making me flustered I have looked back and forth between map and tutorial countless times and I can’t figure it out!

My map VMF is here

Also I don’t know how to make hammer accept a model as being static, I made my own stop sign and Hammer refuses to make it static, so is there a way to make the stop sign be static?