When checking the "Email Deliverability" interface in cPanel it may show a PTR/rDNS error which reads "
All of our servers already have proper PTR/rDNS records setup. This error message from cPanel is a known bug which has been reported to the cPanel development team. This bug will not cause any issues with email delivery and can be safely ignored.
If you have any further questions regarding this please open a ticket with our support department through your helpdesk account.