Can't log in to helpdesk..eternal catch 22 with Chrome and Safari. Change of primary domain name...

Site URL: https://support.squarespace.com/hc/en-us

I have been trying to get proper technical support and every time i was trying to log in the page would refresh and would bring me back to the first one. Since not knowing where to find for help I found my way to this forum and was able to log on.

I have a second question and perhaps I could ask for help here..

We have two domain names and our primary right now has the squarespace website pointing to our primary. In a month we would like to change our domain name but keep our present website..

So my question is how can I get our other domain name to point to our present website? Should I simply change it to our primary?

thx for the help!! SquareSpace Technical Support is such a .....

Good Day!