Same issue here.
The discount codes appear in the admin, but don't work and display that place-holder screen.
...and just to add a bit more detail, I am:
- Using an API version later than '2020-04' (when normal store API discounts started being supported)
- I'm including 'read_discounts,write_discounts' in scope (I think I read that this was just for GraphQL, but can't hurt)
- I'm also creating the discount through a price rule, Ruby code below.
price_rule = ShopifyAPI::PriceRule.create(
title: "name-#{@product.variants.variant_id}",
entitled_product_ids: [@product.id],
target_type: "line_item",
target_selection: "entitled",
value: "-#{@product.variants.first.price}",
value_type: "fixed_amount",
allocation_method: "each",
customer_selection: "all",
starts_at: DateTime.now,
discount_codes: [{ code: "such-and-such-#{@obj.xxx}"}]
)
