ns.piksel.eu has no MX records.
Question and response
Question
dig ns.piksel.eu. MX
Answer
The response has no answer records.
Authority
piksel.eu. 86400 SOA ns.piksel.eu. root.piksel.eu. 2006050902 10800 1800 604800 86400
Additional
. 0 OPT ; payload 512, xrcode 0, version 0, flags 0