koeln1.ntq.info has no MX records.
Question and response
Question
dig koeln1.ntq.info. MX
Answer
The response has no answer records.
Authority
ntq.info. 60 SOA ns.ntf-server.net. ns.ntf-server.net. 2023042236 3600 1200 604800 1800
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0