This is what happens.

I have WPBakery editor on my wordpress site. When I go to 'Edit Post' and paste custom HTML code (adjusted to WPBakery tags) and publish that post everything looks correct. But, when I add new post with Wordpress REST API, through pythons requests library, some parts of web page are moved a bit e.g. list title has 30 px top padding added.. Even weirder is when I click 'Edit Post' for that page and only click 'Update', without changing anything.. updated page looks ok, without any distortion.

Do you have any idea what may be causing such weird behavior? Any suggestion on what to check would be appreciated.