php - WP_Query 'post__not_in' condition is not working: shows all posts

one text

thank you for taking the time to review this.

I am calling a new WP_Query with the following arguments:

$args = array(
'post_type'      => 'post',
'post_status'    => 'publish',
'post__not_in'   => array($featured_post_ID),
'category_name'  => 'blog',
'offset'         => $offset,
'posts_per_page' => 3,
'orderby'        => 'post-date',
'order'          => 'DESC',
);

I know that past issues have been caused by passing a numeric post ID as a variable instead of string; to get around that I am using the following variable definition for $featured_post_ID:

$featured_post_ID = '"'.$post_ID.'"';

When I run this query, it outputs the post I am trying to exclude.

Here is a Transcript of output of the WP_Query to save space. Looks like post__not_in is recognized in the query, but has no effect on the output.

Can anyone advise why this might be happening, or how to fix it?