Why isn't my additional field showing on the product page?

Go to Products → Additional Fields and check these:

• Field is active: edit the field and make sure Active is ticked, then click Save Field.
• Group is active: if the field is in a group, edit the group and make sure its Active box is ticked too.
• Product type: Applies to product types must include this product's type, or be left empty for all types.
• Value saved: on the product's Additional Fields tab, check the value is there and click Save additional fields. Empty values are never shown.
• Placement: a group set to Hook (place on product page) appears at the Hook place you picked, which may be lower on the page than you expect.