All Hooks/Filters Stopped Functioning after update

I had used some of the Woocommerce hooks/filters to customize my checkout page by adding some fields and removing others. After the most recent update NONE of the code I used has any effect on the checkout page. The simplest snippet is here as posted in the functions.php file of my child theme:

/** unset the company field*/
add_filter( ‘woocommerce_checkout_fields’ , ‘custom_override_checkout_fields’ );

function custom_override_checkout_fields( $fields ){

unset($fields[‘billing’][‘billing_company’]);

return $fields;
}

Can someone please explain why this now has no effect when it worked before?

https://www.ads-software.com/plugins/woocommerce/