I somehow jumped over the barrier in level 4 without placing the jewel and then got stuck on the other side. It had already autosaved and there was no way for me to fix it so I had to delete my save file.
Oh no! I hope you kept a backup. There's an option to respawn in the pause menu.
Re-spawning just brought me back to the same side :/ but thankfully I was only on level 4
If it happens again & you're comfortable modifying a little JSON in plaintext, I can point you to where the save games are located.
I somehow jumped over the barrier in level 4 without placing the jewel and then got stuck on the other side. It had already autosaved and there was no way for me to fix it so I had to delete my save file.