How to configure source-magazine in the default theme?

When choosing a website theme, I noticed that the default theme「source」 has three options: news, magazine, and newletter. I want to select the magazine version, but when I select it and return to the editing page, it always shows the default news version. How can I switch this?

Are you clicking “Save” after selecting the option?

/ghost > settings> design and branding (customize) > theme (tab on the right side)