If you have activated our Upsell Popup feature via our app's Settings -> Quickview & Popup Settings, and nothing is showing up when users click on "add to cart", then the problem might be one of the following:

1) You have not added our embed snippet to your theme's product template (or cart template, if showing our popup there). If this is the case, read our theme install article or get in touch.

‍2) your theme's cart type or "add to cart" behavior might be interfering with functionality. In this case, get in touch so we can apply an override. If you're tech-savvy, you can try changing the CSS selector for the "add to cart" button element. More details here: https://help.csell.co/a/solutions/articles/3000089763

‍3) If your popup is displaying only for a few moments, and then redirecting the user to the cart, you might need to disable this redirect feature on your theme, or implement this customization to make the customer stay on the product page once an item has been added to the cart: https://help.shopify.com/en/themes/customization/products/add-to-cart/stay-on-product-page-when-items-added-to-cart
‍If you want us to have a look at possibly disabling this behavior, get in touch!

4) Finally, make sure you are either using/showing Handpicked or Global Product Cross Sells in the Settings -> Product Page, as the Upsell Popup uses product assigned cross-sells to feed the popup ‍

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