I regret that there seems to be some confusion in how the visa lottery is presented to the public. Someone who is selected is a finalist, who is still subject to review. There are many who think that they have one, when they are later determined to be disqualified.
If you have not missed the deadline to challenge the decision, then you may consider legal action. However, such a Federal Court Action can prove very expensive and at times futile. It is unclear whether filing based upon the Administrative Procedure Act is in your best interest without time to review the reason for the denial.
I strongly recommend an appointment or teleconference with an experienced immigration attorney who understands the DV Lottery Visa Program as soon as possible.
The above is general information, not legal advice, and does not create an attorney client relationship.