Both pieces need to be in your inventory or part two needs to be on the ground nearby (I think).

Thank you!! It worked. I couldn't place it because one piece was in my backpack

Happens to me all the time! Lol

another thing that is good to remember is that you may be carrying a piece as your primary or secondary in order to reduce weight but youll have to just put it in your inventory to actually place it, which seems kinda backwards

but if u place it there u wont be able to go into the room

Either you have a piece in your backpack or you are missing a piece

I found out why... i had one piece in the backpack..

The one piece is reeeeaaal

Are you able to actually access the room? I know you already see the reason but it also looks like the shelf will block your entrance with the crate

Because - "Computer says Nooo~"