sorry, I can't provide specific information about the birthday lottery prize in Haidilao. According to some online articles, Haidilao usually provides some special benefits on members' birthdays, such as singing birthday songs, dancing birthday, free birthday cakes, small birthday gifts, etc., and there may also be discounts on 31 yuan coupons and gifts of small dishes or fruit bowls. However, these rewards may vary by region or store. It is suggested to consult the staff of Haidilao directly to obtain the most accurate information.