This is mostly just for the DNS admins and hobbyists out there. If you have domains with web.com / networksolutions.com and you have defined custom nameservers
meaning you put in an IP with a domain name and in the past it updated the root DNS servers then do not change it. The UI will let you change it but they no longer have the ability to update the root DNS servers with your custom nameservers that you or your company manage yourselves.
The NetworkSolutions.com UI will let you do it, but it won't actually do anything. This is per their support team. I do not know when or why they lost this ability. I am also no longer able to call anyone there, it's web chat only.
To be clear(er) this is for custom name servers that you manage yourself, not their name servers and not for DNS servers that are already defined in the root anycast clusters. If anyone is not clear what I am talking about this probably doesn't apply to you.