Play Now Mode in Madden 09 Won't work it says disk unreadable but when i play other modes its perfect any idea?

When i'm playing madden 09 i want to play the play now mode so when i click on it, it starts up then says error disk unreadable but when i play any other mode like superstar or franchise mode it works fine so i was wondering if anybody could tell me what is going on also i have the xbox 360 if that helps