Puzzle 3-8 was invalid, this should now been fixed in both the GB and PC versions. Reminder: if you're playing the GB version your game isn't patched until you start using the updated ROM file, that's up to you.
If you've already attempted this puzzle, you should fully reset your solution by highlighting it on the level select screen and holding the marker button, this will fix it and allow it to be solved properly.
Hotfix - Invalid Puzzle
Source: Steam Community (opens in a new tab)
Build and release context
Recorded Steam release date:
Within one calendar day of this post (UTC). The listed date does not establish an exact launch time.