We are currently running a couple of Facebooks ads that include forms that will sync into our Marketo instance. I noticed that when someone completes one of the FB forms, their Person Source is changed to Facebook Lead Ads. Some of the people filling out these forms are already in our database and have lead source that is getting overwritten. I tried to update the Flow in our campaign to only update the lead source on new records, but it appears that the source is getting updated anyway.
Flow step to update Person Source to Facebook Lead Ads if SFDC Type is empty (i.e. not a lead or contact in SFDC):
However, this lead had its lead source updated even though it was already a Contact in our SFDC instance. I've highlighted the line where the Person Source was changed from Web (General) to Facebook Lead Ads. The other highlighted is the flow step to update the Person Source, which was skipped since the SFDC Type [Person] for this lead was not empty.
Is there any way to block the update on the Person Source/Lead Source field for people who complete a form through the FB lead ad integration?