If marketing emails are being delivered to guests and show the ‘via Sendgrid.net’ after the brand domain life the screenshot below, it is due to the Domain Authentication not being setup. Within SendGrid, the domain authentication may have never been setup or some updates are needed.
Please reach out to Punchh Support if Domain Authentication needs to be setup. See https://docs.sendgrid.com/ui/account-and-settings/how-to-set-up-domain-authentication to get more details directly from SendGrid.
If further assistance is required, submit a ticket to Punchh Support. (For help submitting a ticket, click here)