I have been running a new player on their first and only character through the game campaigns and quests in story order, and discovered that the quest step Decrypting the Darkness, which is first encountered in the Proving Grounds story campaign quest, may bug out. The player obtains the quest step to pickup an umbral engram and decode it at the recaster in order to progress the quest. However, it simply may not work as happened to us. We tried obtaining several umbral engrams through normal play and decrypting it, but it did not work (although some players in forums reported that it did work for them). What ultimately worked for us was to complete the Wayfinder's Compass intro quest steps up to the part where it has a quest step also called Decrypting the Darkness. This enabled us to complete the quest step for both the Wayfinder's Compass campaign quest steps and the Proving Grounds quest step simultaneously. I suspect there is some kind of bug occurring because the exact same name is used for multiple campaign quest steps from different seasons, so I wanted to bring it to Bungie's attention as well as give a possible workaround for any new players that are also encountering this bug. It is not the worst bug ever, but it is certainly disappointing and frustrating to have to break the story order of events just to make the game function properly - not to mention it is confusing to figure out a workaround. Please investigate this issue Bungie, and good luck to other players.