Publish your domain’s DMARC record to avoid phishing and spoofing. For those who’re using a shared IP account from the provider like SendGrid, don’t set up DKIM and DMARC. It forces your mail streams to get “area alignment” that might cause your emails to fail authentication and start bouncing. https://itsupport89999.win-blog.com/6424194/a-review-of-smtp-server