Plesk DNS Email Connectivity Fix

My dedicated server is running Plesk and the mail service for a few domains has suddenly become unreachable. Outlook, iPhone Mail, and Android Mail are all throwing the same “Cannot connect to server” message. I suspect the culprit lies in the MX records—possibly in combination with Cloudflare-managed DNS—but I need a seasoned eye to confirm, correct, and fully verify the entire mail flow.

Here’s what I need you to do:
• Audit the current DNS zones on Cloudflare and on-server, paying particular attention to MX, plus any A or CNAME records that influence mail delivery.
• Adjust Plesk mail settings if you spot mismatched hostnames, SSL certificate gaps, or authentication misconfigurations.
• Validate the fix by successfully sending and receiving test messages from Outlook, iPhone Mail, and Android Mail (I’ll help with credentials and live testing).
• Provide a brief change log so I can replicate or roll back if needed.

This is a one-off task for now, but a smooth resolution could open the door to more ongoing server and DNS work together.