Purchased Choir of One from Xur the last week before all the changes to how to acquire said weapon changed. But no Deepsight Harmonizers were available when the new season was released. Months later Harmonizers were re-introduced through a new Seasonal Archive Monument to Seasons Past. Xur now also sells Deepsight Harmonizers. I have 2 Deepsight Harmonizers in my inventory. 1 purchased from Xur & 1 purchased from kiask (which is the last Deepsight Harmonizer available for purchase until next season) Selecting the Empty Deepsight Socket on the Choir of One results in NO ability to apply either Deepsight Harmonizer that is currently in my inventory.. Selecting ANY other weapon that has an empty Deepsight Socket allows me to see the 2 Items in my inventory and gives me the ability to apply to ANY other available weapon. Weapons locked or unlocked do not change this ability. Bungie needs to put an unlocked pattern Choir of One weapon in my inventory that I can apply whatever catalysts I choose that I’ve unlocked and received at the end mission rewards via the exotic mission encore. Bungie continues to solidify my resolve to sunset my wallet to current and future projects.