DOMAIN_NOT_RESOLVED -- can receive mail, but cannot send

DOMAIN_NOT_RESOLVED -- can receive mail, but cannot send

My Zoho account ( info@tutorvine.ph) cannot send messages to @up.edu.ph domains, but can send emails to all others (Gmail included).

However, the Zoho account can receive emails from @up.edu.ph.

Also, other accounts (Gmail/Yahoo) can send to and receive emails from @up.edu.ph.

It seems the issue is between Zoho and @up.edu.ph.

@up.edu.ph emails are Google accounts and can be accessed using the Gmail app. The following are the mail servers for @up.edu.ph ( http://mxlookup.online-domain-tools.com/):
Target IP Preference value TTL
aspmx.l.google.com 74.125.71.26 1 42 sec
alt2.aspmx.l.google.com 74.125.68.26 5 42 sec
alt1.aspmx.l.google.com 108.177.14.26 5 42 sec
aspmx5.googlemail.com 173.194.202.26 10 42 sec
aspmx4.googlemail.com 74.125.204.26 10 42 sec
aspmx2.googlemail.com 108.177.14.26 10 42 sec
aspmx3.googlemail.com 74.125.68.26 10 42 sec


Would appreciate immediate feedback. What's the fix to this? Thanks.