The mouse-lock issue in FNAF Eternal Nights seems to be a Roblox-style cursor problem rather than a special game setting, and the practical fix is usually to click back into the game window or press the gameā€™s cursor-toggle key if the experience supports one. I couldnā€™t verify a dedicated ā€œunlock mouseā€ control for this exact game from reliable in-page instructions, so the safest answer is to try the standard Roblox/FNAF cursor behavior first.

What to try

  1. Click inside the game window again to re-capture the cursor.
  2. Press Esc and close any menus that may have frozen input.
  3. If the game lets you interact with UI, look for a cursor lock/unlock option in settings.
  4. If the mouse is stuck because the game lost focus, alt-tab out and back in.
  5. In Roblox, some experiences only release the cursor while a menu or chat box is open, then re-lock it when you resume play.

Why this happens

Some FNAF/Roblox experiences use a locked cursor for first-person control, and the cursor only becomes visible or free in specific UI states. That means there may not be a true ā€œunlockā€ feature at all, just a temporary release while menus are open or when focus changes.

Best practical fix

If you want the quickest workaround, try this order:

  • Click the game.
  • Press Esc.
  • Open and close any in-game menu.
  • Alt-tab away and back.
  • Rejoin the server if the cursor stays stuck.

One caution

A few search results mention generic FNAF cheats and unrelated mobile mouse apps, but those do not look like a real fix for this Roblox game specifically.

TL;DR: there doesnā€™t appear to be a confirmed special ā€œunlock mouseā€ code for FNAF Eternal Nights; itā€™s most likely a normal cursor-focus issue, so click the game, use Esc/menu toggles, and rejoin if needed.