Custom page template

I want to make a custom page template (LTR main wrapper on RTL site for specific pages), I copied the custom-page.php from the main theme to the child theme root, but it seems that the theme is not using this file.
Trying to figure out what is going on, I just changed the ID of the main wrapper div, and it did not apply on the page. Did the same change on custom-page.php in the main theme directory, of course it was changed on the website.

What am I doing wrong?