Cert Hostname DOES NOT VERIFY
The error is pretty clear, but you aren't able to interpret it correctly:
Cert Hostname DOES NOT VERIFY (dataxu.io != email.dataxu.io | DNS:email.dataxu.io)
Here:
-
dataxu.iois the hostname on the certificate -
!=it's not equal to... -
email.dataxu.io, your SMTP banner (on220-email.dataxu.iomessage) -
DNS:email.dataxu.iois the DNS name from yourMX 10 email.dataxu.io.
You need to either replace the certificate with a certificate for email.dataxu.io or change your SMTP banner (& DNS MX hostname) to dataxu.io.