“The code worked last week. Now it does nothing.”

A discount’s active dates decide when it can be used. Before the start date it’s scheduled; after the end date it has expired. Either way the code still exists, so the customer can type it, but Shopify doesn’t apply it. In the lab, Shopify gave no reason: the code was simply left off.

LABOLD10 is a lab code that ended on 15 October 2026 after one use. Typed into a cart with one Hydrogen board on 24 October, it got the sentence above; the cart kept only “$10 off $80”.

The same $590.00 cart with another code typed gets another sentence: NOPE123 (no discount uses it), WAX15 (it’s for other products) and VIP20 (it’s only for some customers). Checkout shows the same $590.00 every time.

• Each discount’s status (active, scheduled or expired) and its start and end dates.
• This is the first thing checked: a discount that isn’t active gets this sentence before any other reason.
• Every code typed, and automatic discounts that are scheduled or ended in the last 30 days when they’d apply to an item in the cart.

The discount’s active dates, in Discounts. To use it again, change the end date or remove it; if it shouldn’t be used any more, the customer needs another code.