Hi Saswata,
Thank you for writing in,
Did you copy and paste that content? Probably there is a broken HTML markup on that content. It’s very important to check that as it can affect the other content, you can use this HTML checker here.
If you can’t find any error please provide us the direct page URL where we can see the issue. And if you don’t mind please provide us login credentials in a secure note as well.
That little gap is default margin of recent posts shortcode/element
try this:
[recent_posts count="4" no_image="true" orientation="vertical"]
Is the recent post shortcode on your end has no gap? It could be a side effect of the first issue. Please clarify.
Cheers!