Subdomain Not Working - Site Broken

[bakestl]

I was trying to find my IP address so that I can create a subdomain for a QR code for my site.  I thought I'd set it up correctly -- finding the IP address on Square, and then connecting it to my Google Domains account -- but now my site is broken! 

The site will not load, but only gives a 404 Page Not Found error message. 

How can I undo this -- and then also set up the QR subdomain correctly? 

thanks in advance for any help, everyone!

[bakestl]

Okay... I managed to reset the domain settings on Square so my site came back up, but how do I properly connect a subdomain?

I have it set to:

qr.bakestl.com

A

1 hour

And the IP address was generated by Google, and is getting the error message.  Is this what takes a day or two to generate??  There's no extra info on the error page, so I'm not sure.

~~~ Thanks !