If you provide us details of your domain registrar, we may tell you that we actually need access to a different registrar or system. This is because your previous web design studio may have changed the registrar’s default nameservers to that of another system to suit their own internal processes. Without getting too technical, it’s the nameserver that controls which DNS settings are used.
When you change a nameserver it will take a few hours for the change to take place, and you will loose all existing DNS settings. This makes it more likely that emails and third party services will go down. We prefer using the default registrar nameservers, but encourage leaving the nameservers where they are and not changing them in order to reduce complications going live.