Hi there,
yes I did work it out and I’m surprised it wasn’t something ever discussed on any forum I’ve seen.
for my store personally, I use a product options app as my products have quite a lot of variations to add or reject when purchasing a product. When the customer was purchasing a product with a price add-on option, the app was using ‘draft’ orders and this is when you see the ‘gift card’ option instead of ‘discount or gift card’. Draft orders also don’t work for automatic discounts.
so in short, if you have an app on your store that uses draft orders in the background this would be the issue. I am not aware if this is the case for everyone who is having the same issue but it would be good to investigate.
hopefully this helps you in some way.
Elise