I doubt they have fixed it and I doubt they have plans to, but in the off chance they have make sure it is prefixed with dns(number) or ns(number) as they will

I doubt they have fixed it and I doubt they have plans to, but in the off chance they have make sure it is prefixed with dns(number) or ns(number) as they will not give you a useful error message if you have not done so. e.g. ns0.yourdomain.tld but that probably won't work either. I used to use bare apex domains for a couple decades but they and several other registrars stopped supporting that. They do not give useful error messages to the clients or to their support. AFAIK there is nobody left that knows how to debug the back-end. This is just a suggestion but I would consider moving the domains somewhere else. It seems web.com is just hoovering up registrars but not migrating everything to a centralized, modern, maintained system. In my experience and opinion they do not know how the back-end of the old Network Solutions systems work.