I recently I.ported a cpanel account onto a debian 9 apache server that also hosts email (postfix & dovecot) If on my server I do dig mx client domain.com it returns the old mail information. However, if I go to mxtoolbox.com in a web browser, the SOA is the new registrar dns and mx record is my server (server1. domain.com) Also, if I add mx record server1.domain.com ...email for domain stops working, however if I use mx record mail.clientdomain.com email works again. I have another client on same system, account not imported from cpanel, where mx record is server1.domain.com and their email is working. Apart from the mx records and different domains, both domains DNS records are identical format. The client with the trouble had their website moved to my server a few days ago and email moved to my hosting yesterday. Anyone got any ideas on what can cause this? If it was caching or TTL, why is mxtoolbox showing my server?