An “NameServer” record indicates which DNS nameservers are authoritative for the domain, i.e. which servers should be queried to lookup the values of all other records (such as A, CNAME, MX etc.)
The nameserver records for your domain are set at the Domain Registrar level (where we register and pay for your domain). The registrar then delegates to our nameservers. Please see section “Changing Nameservers records” for making changes to these.
example.com NS dns1.tibus.net
example.com NS dns2.tibus.net