WP Editor Doesn’t Display Ona Theme

Hi, I have the Ona Health theme activated on my website. When I try to edit different pages via ‘Editor’ in my WP menu on the left hand-side, the page pops up to edit, but shows a completely different theme. The only way I’m able to edit any of the pages of my website is if I choose ‘Edit site’ from the WP toolbar at the top of my website page.

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