Your theme has altered the normal ordering of the WordPress filters such that the wpautop filter is run after shortcodes are parsed. The result is that extra
The solution is to move the wpautop filter so that it’s run before the do_shortcode filter. Your theme possibly has the code shown below somewhere, a good place to start looking is the functions.php file then any shortcode related file, find this code and remove it.
remove_filter( ‘the_content’, ‘wpautop’ );
add_filter( ‘the_content’, ‘wpautop’ , 99 );
add_filter( ‘the_content’, ‘shortcode_unautop’, 100 );
If you can’t find it, the author of your theme will be able to tell you how to do this or provide a workaround.
You can email the author of the Mercor theme at firstname.lastname@example.org