EnigmaticManiac

I've had the same thing happen to me with multiple backpacks (Multiplayer on Xbox Series X with PC as host.)

Was never posted in patch notes and the description still listed it as a "giant hammer". Looks like they've since changed the description to "giant mallet". I would say it was still a bug when the description still said hammer...

I will have to try reloading the game save because I'm running into the same issues with the switches. (Multiplayer game on Xbox Series X on 12/16/2020). Update (12/18/2020): Reloading the save file worked. Was able to activate switches and gain access to underwater lab. Still tons of doors mysteriously locked.

I'm having the same issue as well. Could not break apart sap, acorns, or pebbles using the Mint Mallet. I was able to break these apart using an Insect Hammer in the same game. (Multiplayer game on Xbox Series X on 12/16/2020).