Check that the data-config in your HTML code contains productID (capital ID) and NOT productid (lower case id).

Check that you are using the correct productID .

Check that the product is enabled for that checkout and that there are not any blacklists.

📗 TIP

Path to setting: Web Checkouts -> [your checkout] -> press Edit Details -> Allow All Products

The following set up enables all of your products on the checkout.

Check if your product has Web Checkout enabled in the Availability section of the product detail.

If it is a backend connected product, make sure all of the values in the Mapping tab are filled in. If the web checkout contains such a product, the product list will not be displayed.
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