backpack slot unacceting

[Faulyn]

a few days back an item (gnat fuzz 5) was trashed from my backpack

  and now i can not place anything in that slot 

not even gnat fuzz 

anyone know how to remedy this?

 

[McSquirl Nugget]

there's a bug where it doesn't show anyting in that backpack slot.  I've had this happen with other materials i've trashed.  I've had it work after sleeping,  at the worst i've had to log out and back in.