Hello
Microsoft now requires volume senders to have SPF, DKIM and DMARC verification/DNS records set up on their end. If it is wrong, or missing, Microsoft can reject them, as there's no way for Microsoft to verify that they are who they said they are.
Since not all email service are requiring SPF, DKIM and DMARC at the same timeline, or threshold, so it is possible that you can receive them via a different email service. Since you did receive it, can you try to get the email source/header, so that I can see what email service referrals.selectminds.com uses to send their email, and compare with their public SPF record, to see if that might be the issue.