I noticed this issue where I had to refresh my browser each time I fell because I was stuck in a box.
When the player falls try having them teleport back to the initial position rather than trapping them inside a box. You should be able to create an object, hide the object, set up a collision event, then teleport the player back to the original position using their previous x and y coordinates. There's probably a simpler way to do this, but I haven't touched GDevelop's scripts in a while.