spf.maychuemail.com has no MX records.
Question and response
Question
dig spf.maychuemail.com. MX
Answer
The response has no answer records.
Authority
maychuemail.com. 3600 SOA nsbak.pavietnam.net. hostmaster.maychuemail.com. 2025091912 14400 3600 1209600 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0