1. "Allow Custom Gift Card Amounts" is already turned on.
2. When I go to your app and I cannot see any "option" along with the preset amounts
it should be there when you are actually loading a card. i.e. after you have swiped a card to load.
The only message is "Card not stored: add at least on item"
that sounds like you are trying to add a "card on file" when I see the error that says about storing.
https://squareup.com/help/us/en/article/5432#sell-your-gift-cards-with-square
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