When you say you cannot access them, what do you mean? Are you getting an error code/message?
Did you download the content from within the game, or from the Xbox Live Marketplace?
If you downloaded it from the Marketplace, you will indeed want to give
Phone Support a call and pursue a refund, as the details state this content must be purchased through the in-game store, and NOT the Marketplace.
Let us know, and we can go from there.
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