A nameserver controls what servers will handle DNS for your domain (domain to IP mapping). Nameserver settings for your account with us are ns1.lithiumdns.net with the IP address 18.104.22.168 and ns2.lithiumdns.net with the IP address 22.214.171.124.
It is recommended that you use our nameservers, so you can take advantage of the DNS Manager within the control panel as well as our automatic DNS provisioning.
Nameserver changes are made through the company through which you registered the domain. If you are unsure, you visit http://whois.sc/<domain>. For example, to find out who the registrar of apnscp.com, visit http://whois.sc/lithiumpanel.com. Look under Whois & Quick Status > Registrar. This is the domain registrar responsible for managing your domain.