You should schedule an appointment with an immigration lawyer, and provide the lawyer with a copy of the decision you received. An immigration lawyer can help determine whether or not you can still appeal, and can prepare the appeal for you. Make sure you save the envelope you received the decision in, which should indicate when the decision was mailed. Best of luck to you!
The above is general information and does not create and attorney-client relationship.
Julie Kruger, Esq.