How to I update custom fields on the Membership / Subscription object from the related Payment Txn?
Subscription is the one of few objects that doesn't work with like to like API field name copying in Payments2Us. However, with a simple flow on the Payment Txn (status equals Matching Complete - so it will not impact any payments and subscription not equal to null) that can then update the subscription record with the relevant field (e.g. Campaign).
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