The nameservers you use vary depending on which server you are hosted on as follows:
HYPERION:
ns1.nethosted.co.uk
ns2.nethosted.co.uk
LUNA:
ns1.nethosted.co.uk
ns2.nethosted.co.uk
TITAN:
ns21.net-hosted.com
ns22.net-hosted.com
MERCURY / PLUTO / MARS:
ns1.nethosted.co.uk
ns2.nethosted.co.uk
If account setup pre 2023:
ns19.net-hosted.com
ns20.net-hosted.com
NEPTUNE / SUN:
ns1.nethosted.co.uk
ns2.nethosted.co.uk
If account setup pre 2016:
ns3.net-hosted.com
ns4.net-hosted.com
URANUS:
ns5.net-hosted.com
ns6.net-hosted.com
SATURN:
ns7.net-hosted.com
ns8.net-hosted.com
JUPITER:
ns9.net-hosted.com
ns10.net-hosted.com
EARTH:
ns13.net-hosted.com
ns14.net-hosted.com
VENUS:
ns15.net-hosted.com
ns16.net-hosted.com