Npcs can also hand you a none… but they are buggy so that’s to be expected.
We used to be able to remove a none from our inventory by activating it. Sadly this method no longer works for reasons I don’t understand.
Maybe this will work. Maybe. This method is untested but it can’t really do any worse.
Hold a few batteries, less then you need to fill a tool.
Use [=] to swap its letter with the none/blocked object.
Reload the tool to remove the batteries from your inventory.
This probably wont free up the slot the none will indefinably hold in your inventory but it should give you back the item that the none is blocking.
I don’t have the game here so let me know if it works.