ME3 original disc set won't install due to origin being offline

Hi there, please note that the serial code can only be redeemed in one account. If it shows it's already used, then it has already been redeemed on a different account. In case you bought this second-hand, I suggest that you talk to the retailer or the person who sold you the game. If it was a new, sealed copy, please contact EA Help for further assistance.