Unable to set up Custom Domain on Google Sites despite purchasing it on Google

I'm setting up the website for my new company but I'm having issues configuring the site. Whenever I try creating a new site on Google Site, the Settings popup doesn't show the Custom Domain category, regardless of whether I'm logged in as admin or as a normal user. On Squarespace I can confirm it's telling me "Google Workspace is already managing this domain. Any changes to the settings could impact its functionality. Learn more." and I see a bunch of records below that.

However, I'm still not seeing Custom Domains as an option in sites.google.com when I open a Site and I've confirmed that Sites is enabled in Admin Console and under Domains in Admin Console, the domain shows up as "Primary Domain".

Am I missing something here?

Oddly enough when I