Vorjego

So, I keep getting mods for my gear, and I want to upgrade so I go to upgrade them. When I get there, it won't even show me the mod I received as if I never even got it. It is frustrating when I find a mod that is better than the one, I have and can't equip or even upgrade it. It is a bug in the game. I would really appreciate some help with this. Thank you.