Email was rejected because of DMARC policy
I use iCloud for person emails and I have noticed lately that some messages that were sent to me were never delivered. I have received some letters from financial sites to say that an email to be was undelivered, and I recently did not receive an activation code from my state's COVID immunization site. I managed to track that last one down and discovered that iCloud reject the email because of he sender's DMARC policy.
Does anyone know how to resolve this problem, and if Apple's email filtering may be too restrictive in this respect? I assume that the COVID emails are successfully sent to many other sites.