Does post purchase offer work with PayPal?
Monk's post purchase upsell/cross sells are powered by the official Shopify checkout extension. To get your offers to show up for customers paying via PayPal please make sure automatic billing/automatic payments via PayPal is set-up on your store. When you activate PayPal on your store, Shopify asks PayPal for "Reference Transactions" approval on your behalf upon auto-detection of Monk app (read full Shopify doc here).
Please follow these steps to check if this is set-up on your store:
1. Go to Settings on your Shopify admin dashboard
2. Under Payments, choose PayPal Express
3. It should show "Approved" - if it shows "Pending" please wait for 72 hours and check again
4. If stays "Pending" even after 72 hours we suggest you contact PayPal support
"Approved" implies that the post purchase offers should work as intended on your store.
If you still face any issues, feel free to write to us at firstname.lastname@example.org & we'll do our best to help :)