There are some instances when the free gift is not added to the Sales order
1.A free gift cannot be added to an order automatically if mandatory information regarding the free gift is missing. For example, a free gift promotion offers a warranty that requires a value to be entered in the Amount column in the Items list.
The free gift appears on the Items subtab but is not added to the order until the missing information is entered. On the Promotions subtab, the Eligible Free Gifts column will indicate that there are free gifts eligible to be applied to the transaction, but the Free Gifts Added column will display zero.
2.Customer eligibility criteria is defined by the search or group selected under the audience subtab of Promotion record. If the customer is outside the search result: then also the result will be the same.