Issue auto generate

I have your plugin installed. Use everything completely normally. But this article alone is encountering an error, which is a problem with automatically generating table of content. It displays at the top of the header. I don’t understand why it is like that? I tried debugging in the code but it encountered the following cause:

• I noticed that when I var_dump($content) in function boomdevs_toc_post_types() in other articles, it will display the content on the page including footer and header, but for this article, it returns the content. Content on a blank page does not include the footer and header of the page. I think this is the cause but don’t know why.
• I tested it in a local environment with the same code and the same database, everything works normally.
• I have provided you with images of me inserting var_dump() to debug and comparing between 2 normal and error articles.

The page I need help with: [log in to see the link]