Purview DLP and Internal/External

We’re just setting up M365 and it was requested to have DLP configured before moving mailboxes up. We’re doing exchange hybrid and ran the wizard earlier and using central mail transport.

Not sure if DLP is supposed to do this but we have a rule configured that says “only with people inside my organization” and I sent a test SSN to my cloud mailbox from my GMail account and it’s triggering DLP. I thought it would only hit if my cloud mailbox was trying to send out? Not receiving.

My GMail also gets a bounce back saying I violated my organization policy which makes me think DLP thinks my GMail is internal and not external.

Is this correct or is something messed up somewhere? We have the default connectors so not sure what might be broke.