Mails going into Span!

You might look at using the SendGrid option as your “Send With” option. That tends to cut down on your mail’s identification as spam in the first place. And they have options for verification that should cut it down even more.

What @carolwp said is right: https://support.mailpoet.com/knowledgebase/send-with-smtp-when-using-a-professional-sending-provider/