Q&A: How do you meet the Prothean in Mass Effect 3?

I downloaded the DLC “Ashes” in Mass Effect 3. But when I replayed Mass Effect 3, I didn’t get to recruit the Prothean or try out the mission. I have an Xbox360. I don’t know if I require to download once again or perhaps I missed some thing even though playing the game. Can someone aid me on this?