A product is still selling past its threshold

If checkout is not being blocked below your buffer, it is almost always the checkout rule that has not been activated. Here is the full checklist to fix it.

Updated July 22, 2026

If a product is still selling below your buffer, work down this list. The first item is the cause in most cases.

Check these in order

Is the checkout rule activated? The block only works once you add the Easy Stock Buffer rule in Settings, then Checkout. If the dashboard shows "Stock blocking is not active", that is your answer - see activate stock blocking in your Checkout settings.
Did you test at the cart or at checkout? The cart page deliberately shows the message but still lets shoppers edit their cart. The block itself is held at checkout, so test by proceeding to checkout, not just by looking at the cart.
Is the threshold above 0? A threshold of 0 means no protection for that variant. Open the variant on the Thresholds page (/app/thresholds) and set a number of 1 or higher.
Does the variant actually have a threshold that applies? Check the Source column on the Thresholds page. A variant with no per-variant threshold, no matching bulk rule, and no shop default is never blocked.
Is Shopify tracking the quantity for the variant? The block needs a stock count from Shopify. If a variant is set to not track quantity, there is no number to compare against.
Is pause on? If you paused thresholds for a sale, everything is allowed through until the pause ends. See pause all thresholds.
Did you just change stock? The app refreshes its stock snapshot when Shopify reports an inventory change. Give it a moment after a big edit, then test again.

Good to know

Once the rule is active, it covers every threshold you set - you never need to add it again. For a deeper look at exactly when a line is stopped, read how the checkout block works.