Ammo Wrangler + Longinus

[JoHo]

So at the improvement menu, it says that the improvement "Ammo Wrangler" which lets you reload significantly faster is locked and I need to "Finish 1 Longinus Quest" But I did! I did the Longinus Quest where you go to the Himalaya and search for some diamonds. What the hell am I supposed to do?

[Bluemoon]

that's just the intro to his quests

basicly: do one more ;-) (and 3 repetetive - almost exact the same missions afterwards zZz)