The drop-down doesn't have my item.

The drop-down lists show a limited number of items.  Sometimes the entire list can be shown, but longer lists may be cut off. If you can't find the selection you need in a drop-down, start typing the name in the selection box to alter the available items in the drop-down list.

If the item you need is not available on the list, you may request to add an item to a drop-down list by contacting the OST.