Items glitching/disappearing - To fix that, load your last saved game; it should restore the item to its original place or your inventory.
Cash register key (cat) disappearing - Load your last saved game and see if this fixes it; if you’re still unable to find it, please reset the game progress from Settings or wait for a patch.
The fish head does not respawn - Our team is trying to fix it as soon as possible. Until then, the only fast way to continue would be to reset your progress. Before doing so, please make sure that it has not been restored to its original place.
(Switch) Partially different content compared to other platforms - Rest assured that our team is doing its best to have similar game versions on all platforms as soon as possible.
(Xbox) Crashes on Night 4 in the attic/loft of the museum; Fixed - Please update your game.
(PC) Game crashes - Please ensure that your PC meets the minimum requirements and that your Windows and GPU drivers are fully updated. If that doesn’t fix it, then follow the instructions here.