mx.gadsa.es has no TXT records.
Question and response
Question
dig mx.gadsa.es. TXT
Answer
The response has no answer records.
Authority
gadsa.es. 7200 SOA ns1.acens.net. hostmaster.ns1.acens.net. 1772570818 14400 3600 604800 7200
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0