How do I switch my squarespace domain to the website I designed

I recently created a website and it doesn't have the domain that I purchased because I switched templates causing me to create a entirely new website in my account dashboard. How do I switch my domain without having to start over from scratch? Please help!

I would contact squarespace here

1. Confirm that you're logged into the correct Squarespace site.
2. In the Home Menu, click Settings, and then click Domains.
3. Click Use a domain I own.
4. Enter the full domain name you're transferring in the Domain Name box, and then click Continue.