How to select custom image size?

Hello dear friends.
I created a custom image size (width this line: “add_image_size( ‘category-thumb’, 2731, 1024, true );”) but could not find how to use it with “Advanced Category and Custom Taxonomy Image”

Thank you for your help.

Below is the code I have:
=========
<img src=”<?php
foreach((get_the_category()) as $category);
$taxonomy_img = get_taxonomy_image( $category->cat_ID );
if ($taxonomy_img == “Please Upload Image First!”)
{
echo get_template_directory_uri(); echo ( ‘/images/cat_img.jpg’ );
}
else {
echo( $taxonomy_img );
}
?>”>
=========

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