If a Meijer.com coupon code isn't working, ensure the code is entered correctly without any typos. Check the expiration date and any specific terms and conditions associated with the coupon. Verify that the items in the cart meet the minimum purchase requirements and are not excluded from the promotion. Ensure the coupon hasn't already been used, as most codes are limited to one-time use. If the issue persists, contact Meijer customer support for assistance.