Tamir Informer Escort Challenge (Damascus)

[Missi G]

I have an issue with this challenge. I completed it, but when it was time to receive the reward, there was nothing there in the scene and then I was stuck in the scene...I couldn't get out of it unless I exited out of the game completely and now when I go back to do the memory, I have to start from the total beginning. Because I've already completed the memory block...but i wanted to go back in and complete all of the other objectives...so can anyone tell me how do I fix this issue when I become stuck in a mission?