Category dropdown doesn't show up in mobile setting

I have a category that has some sub categories.

https://imgur.com/a/zF7BRUS

as you can see in the first picture. It shows dropdown in normal page.

But it doesn’t show the dropdown in mobile page(picture 2)

I pointed that the category list derived by

‘/wp-content/plugins/td-cloud-library/shortcodes/category/tdb_category_sibling_categories.php’

I’ve tested several changes in the file and it can be shown in the normal page.

But as I mentioned above, it doesn’t appear in mobile page.

I tried make a mobile template for the category(originally the category doesn’t have mobile template),

and it seems like reference same file(picture 3, 4)

But actually the mobile page didn’t reference the short code.

Please advise me what file I need to change to display the dropdown.