Recurring Payment IPN variables confusion.

[Tatva_User]

Hi, I have created subscription type of products in Magento 2.2.5 CE. And when i tried to purchase subscription type product( recurring payment type) paypal returns three IPNs.
- 'txn_type' = cart/express_checkout(some times)
- 'txn_type' = recurring_payment_profile_created
- 'txn_type' = recurring_payment
The first one contains 'invoice' - magento's 'increment_id' but other two don't. Instead they contains 'rp_invoice_id'. My questions is how can i decide that all three IPNs are for the same order.

Thanks

[Areliven]

There should be a txn_id field that would be the same for every IPN associated with a transaction.