Why would email deliver normally when MX Lookup test returns "DNS Record not found"? [closed]
Your domain does not have an MX record. But an MTA is listening on the A record's IP, and that is the fallback of SMTP in case there is no MX record.
Your domain does not have an MX record. But an MTA is listening on the A record's IP, and that is the fallback of SMTP in case there is no MX record.