For anyone facing this issue recently and using an email service like GSuite or AWS SES, the following link Configure private email relay service from Apple's own documentation helped me a lot. Especially the last part of that link: Configuring Your Email Service Provider (ESP) Account SPF TXT Record for example.com to support using Amazon SES example.com. IN TXT "v=spf1 include:amazonses.com ~all" Also, it looks like Apple needs the SPF record to be a TXT record, and not the traditional SPF type of record which is still available in all DNS providers but all of them have marked it as deprecated. Hope this helps someone!!