Why is my coupon rejected when it worked before?

Most likely a redemption limit has been reached, or the campaign is no longer active.

Check the following:

• Limit per code: the code has reached its maximum number of uses
• Limit per customer: this customer has already used the coupon the allowed number of times
• Limit per time frame: the maximum number of uses for the period has been reached
• The campaign End Date has passed
• The coupon or campaign has been disabled

👉 Go to: Merchant Tools → Online Marketing → Coupons and review the redemption limits.