ms.mailcloud.com.tw has no TXT records.
Question and response
Question
dig ms.mailcloud.com.tw. TXT
Answer
The response has no answer records.
Authority
mailcloud.com.tw. 900 SOA ns-848.awsdns-42.net. awsdns-hostmaster.amazon.com. 1 7200 900 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0