Weapon mods stuck in Stash

[BuLLeTSpOnGe]

My weapon mods seem to be stuck in my Stash, and I can't move them to my inventory?  I didn't put them all in their either, and think they may have been moved off of weapons I had stockpiked them in (although those weapons seem to be missing now as well?).

Thanks for the help

 

[PropaneCrazy]

Could be your backpack hasn't the room for them