To use Zipify OneClickUpsell for Post-Purchase Upsells you will be required to select "One Click Upsell - Zipify OCU" as your active post-purchase app in your Shopify admin "Checkout" settings before we're able to show one click post-purchase offers to your customers.
Follow the quick and easy steps below:
Navigate to the Settings > Checkout section in your Shopify admin
On the next screen, scroll down to the "Post-purchase page" section there
Click the radio button next to "One Click Upsell - Zipify OCU" to select it
Click the "Save" button to save your Checkout Settings
Please reach out to us in Support Chat if you have any questions we can help with!