Manager Forum Emails not being delivered

I have recently changed the mail server to drop emails that don’t have a valid ptr record as 99% of the time emails with no valid ptr record are usually spam/malware etc.

However, I have found that the emails from Manager forum are no longer coming through. Would you be able to setup a Dns Ptr record for these emails. This will also ensure that the emails are delivered for Gmail, Aol and Office 365 as these mail servers also drop emails with no PTR records.