There are normally 2 cases when checkout-boost offers don't show up:
Case 1: Your store doesn't have a cart page, but the setting is "Show offer on cart page".
After customers add a product to cart, if your store has a quick-shop function and directs customers to checkout page instead of cart page, it is suggested that you choose the setting "Show offer after customers add matched product to cart"
Case 2: You have tested your offers consecutively, and the offer did not show on the second test
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