campaign bug

[foehammer]

hi, I played the second mission(requiem) with my brother on co op legendary we started one day and finished it the next, but it says that we haven't even played the mission yet. this is a pain in the butt because we spent a lot of time on it. also i played finished dawn on legendary solo and did not get the challenge. please help me out with this because if this keeps happening it will take the fun out of the game and i will not want to play. I'm sure other people have complained about similar topics. thank you.