Ok so, I have been badly affected by a lore challenge glitch and I don’t know if everyone is being affected by it or not. The glitch is that if I make progress for a lore challenge, and then fail the story mission, the progress is saved in the lore challenge menu but not in the career challenge menu. This can fool the game into thinking you have completed the lore challenge in the lore menu, but not in the challenge one. I have suffered from this, as my Deande has been disabled from getting her Legendary item.
Onto the prevention. Everytime you fail a mission, clear you cache. It lets the system know that the progress is there and brings it all up to date so it is all equal. However there is no way to comeback from the lore menu completing a challenge, but the careers one not saving this progress. The game disables that challenge from being completed. I am contacting 2k support on this glitch being fixed, so there may be an easy solution.
If Gearbox are reading this though, please allow us to redo lore challenges from the career menu. It really is annoying wjen trying to master a character and this gets in your way.