Problems with dlc citadel

I made a mistake downloading the 2 part before the 1 part, and i made a mistake deleting number 2 from my storage device, trying to download again 2part to number 1part be reconagize. But everytime i try to download number 2 it says download complete but when i try to play it says number 2 part is needed, If i search it on my storage device it doesnt apear even that my history download Said that is completed everytime i download again. What can i do to play dlc citadel?