Copying a custom theme

Hi there,

Apologies if this has been answered already – I’ve done some research and could not find any questions relating to my specific situation.
I have just inherited the role of administrator of the website at my new job.

Currently, we have custom themes built using php on our site. Specifically, we have a newsletter section of our site and I was looking to create another page that looks identical to this existing page. Our newsletter theme has some custom divs with content living inside that I did not want on the new page I was building, so I copied the .php file and renamed it to match the new page I’m building. Edited the code with some comments to get rid of the content I do not want on the new page. Everything looks great on the new page, but my issue is this:

When editing the new page, when my new theme file is selected, there is no content visible on the edit section. When changing the new page’s theme back to the newsletter theme – I can see the content as ‘newsletter content’ on the edit page.

Basically, when editing my new page – I cannot see any of the content that exists on this page until I switch the theme back to the one I copied from. Then the content shows up on the edit page.. Once the content is the way I like, I must switch the theme back to the new one so the page looks correct.

This can’t be the correct way… Anyone have any suggestions?
Thank you very much