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There are five PayPal specific requirements that must be passed to Import Order:
paySource = 'PAYPAL'
paypalBillerId forceMerchantId = the value assigned to your PayPal Commerce gateway, found on your gateway list.
salesUrl = the url of the checkout page
redirectsTo = the url of the page in your funnel that PayPal will redirect to on a successful transaction.
errorRedirectsTo = the url of the page in your funnel that PayPal will redirect to on a cancelled transaction.
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Upsell Pages
Step 3: Import Click
After a successful Confirm PayPal callcheckout, the customer proceeds to the next page in the funnel, 'upsellPage1', and another click is imported using the Import Click endpoint.
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