pelagoo

Hello, I have created an email campaign in Squarespace. However, when I enter the sender profile information, it says Unverified domain may be marked as spam. After trying a test (before importing all our member emails), the email does get delivered but indeed goes into the junk mail folder. We used squarespace for our domain, however, we create our email accounts thru google. What can I do to verify this? Thanks in advance!