The issue for both stems from challenges, the source of many attachments and camos in Vanguard, which are either incompletable or fail to register progress. As it stand right now, players looking to create the perfect gun are having to navigate around these issues until a fix is implemented.
Call of Duty: Vanguard - Assassin Proficiency isn’t available.
This first major bug is an issue affecting a specific challenge for the Automaton assault rifle, which has in turn led to a domino effect for all assault rifles in the game.The challenge in question is for the Mind Games camo for the previously mentioned Automaton assault rifle. To unlock this camo players need to score 10 kills with the weapon while it has the Anastasia sniper barrel, Embrepp Broadsword stock and Assassin proficiency attachments equipped. This would be simple enough, but when players went to equip the Assassin proficiency, they found it didn’t exist. This one small issue gets far bigger if you step back and look at how mastery camos are unlocked in Call of Duty: Vanguard. Without the Mind Games camom, you cannot unlock the Gold camo for the Automaton. This then prevents you from unlocking the diamond camo for assault rifles, as the prerequisite for that mastery camos is that all weapons in a specific category like assault rifles must have the gold camo unlocked. As it stands right now, the Automaton and it’s missing Assassin proficiency is acting as a bottleneck for all other assault rifles from sparkling with an impressive new camo.
Call of Duty: Vanguard - Reticle unlock bug
The second, and perhaps most significant for the actual gameplay experience, is the glitch preventing players from unlocking additional reticles for their chosen weapon. This issue is far simpler to explain, as it appears to be an issue with how the challenge progression for unlocking new reticles is tracked. Getting down to specifics: to unlock reticles you need to earn kills while aiming down sights, which sounds simple enough! However, due to this bug the progress bar doesn’t fill up regardless of how many kills you get while doing so. For now, it may be best sticking to short range weapons like the MP40 until a fix is implemented. While Call of Duty: Vanguard has been well received overall, it hasn’t come out the gate totally spotless. One such example comes from the Zombies community, which has been highly critical of the new Der Anfang map and its various issues.