Category ID Trouble in Theme

I am having trouble after upgrading WordPress to the latest version, differentiating between categories, and having them display accordingly.

URL: https://www.kartsportmagazine.com/index.php

In the past, prior to updating, any article written in “Feature Stories” would appear in that column, and likewise for “Industry News” – now regardless of the designated category, it doesn’t work.

In the home.php file we used to have it set up as:

<?php $wp_query->set( 'cat', '-2' ); ?>

and

<?php $wp_query->set( 'cat', '2' ); ?>

But for some reason that’s not working. I’d be grateful if anyone were willing to help me. I can PayPal some money to someone if it’s a paid deal or whatever. I just need to get this resolved very quickly. Thanks so much in advance:

Link to them, if necessary:
https://clients.eyenovation.com/downloads/kartsport_theme.zip