Donations app handling of payment gateway payment notifications unrelated to subscriptions stored in the Donations app

The Soapbox Engage Donations app can be configured to record recurring payment transactions sent to it from payment gateways.  For example, if a donor has scheduled monthly recurring donations to be made to an organization, the future monthly payments processed by a payment gateway can be stored automatically using a webhook or other notification sent by the payment gateway to Soapbox Engage.

There may be situations where an organization has recurring payments processed by a payment gateway that should not be recorded by Soapbox Engage.  For example, recurring membership payments might be processed through a different solution, and should not be treated as recurring donations within Soapbox Engage.

To handle these scenarios, the Donations app ignores any notification from a payment gateway that is not related to an existing recurring donation (or "subscription") within the Donations app.