Found the fix.
Just had the same thing myself today
UPDATE
Nevermind sorted now, found it just to the west of Anchorite Base on Jedha. I assume the pieces/materials locations are randomised (or I was looking at an old guide!)
Timestamp 1:37 on this vid: https://www.youtube.com/watch?v=pHi9TjhmuvA
Sadly, not a fix for me. As I said I did open that chest, I got the notification about the material unlock, and still no dice...
Found the fix.
What was the fix for you because the same thing happened to me, and I'm seeing a couple others too have the same problem
For me it was/seems that the chest aren't fully randomized! All chests pertaining to a specific "set" are in the same place for everybody, but the materials and the jacket were switched, as opposed to what I had seen in videos.
