Custom field on Payment object automatically filled out when Opportunity is created

Question

My organization is using the Salesforce npsp (non profit success pack). We use the Opportunities object for both donations and grants and separate the two by different Record Types.

When someone creates a grant or donation Salesforce automatically creates a Payment record as well. This is standard functionality for Salesforce.

On the Payment object we have a custom field called "Scheduled Date" whose data type is just a date. When the automatic payment is created because someone created a donation or grant somehow the "Scheduled Date" field is automatically filled out with the date from the Opportunity "Close Date" field.

I've checked the following Salesforce Automation systems looking for some configuration that would automatically update this field but I can't find any:

1. Workflow Rules
2. Workflow Actions - Field Updates
3. Flow

When I go to the Payment object's "Schedule Date" field and see where is this used I don't see anything there (hoping to see it showing some automation system there).

Here is what the field looks like on from setup:

I would appreciate any insight into what is causing this field to be automatically filled out.

UPDATE Someone suggested me checking the Nonprofit Success Pack Settings which can map Donations to Payment Mappings as per this documentation: https://help.salesforce.com/s/articleView?id=sfdo.NPSP_Configure_Opportunity_Payments.htm&type=5 I logged into SF and checked the Donations->Payment Mappings configured and there were no configurations set up to map Donation field "Payment Date" to the Payment field "Scheduled Date". Here is an image of what is configured:

Answer 1

According to docs,

Map Opportunity Fields to Payment Fields

Use Payment Mappings to automatically copy values from Opportunity record fields to Payments, whenever you create a new Payment. You may want to do this so that details from the Opportunity record also appear in the Payment record for easy reference or billing. Salesforce executes the mapping for automatically added Payments, as well as Payments created through the Payment scheduler. Manually created single Payments will not use the mappings defined here.

Payment mapping requires that you have two fields (one on Opportunity, one on Payment) of a matching type in order to create a mapping between them. When you create a mapping, information from an Opportunity field displays in the mapped Payment field, but not vice versa. In other words, information from Opportunity fields can appear in Payments but not the other way around.

Steps

1. Click the NPSP Settings tab. If you don't see the tab, find it in the App Launcher (App Launcher icon).
2. Click Donations | Payment Mappings.
3. Click New Payment Field Mapping.
4. In the Opportunity Field list, select the Opportunity object field you want to map from. Once selected, all the fields of the matching data type on the Payments object are shown in the Payment Field list
5. From the Payment Field list, select the Payment field you want to map to. In the example below, the administrator has created a new field in the Opportunity object called Payment Type. When you select Payment Type from the Opportunity Field list, you can choose any field on the Payment object that uses the same data type.
6. Click the Create Custom Mapping button to complete your mapping.

You need to check this mapping to figure out the population of fields on payment record.

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