mx.zeptomail.com has no TXT records.
Question and response
Question
dig mx.zeptomail.com. TXT
Answer
The response has no answer records.
Authority
zeptomail.com. 600 SOA NS1.ZOHOCORP.COM. dnsadmin.vtitan.com. 2026022301 7200 1800 1209600 1800
Additional
. 0 OPT ; payload 1280, xrcode 0, version 0, flags 0