want to hide billing first name text box

it was working fine with code i added in functions.php file, but after updates now billing first name text box is not getting hidden. it always displays and its confusing for my clients what to put into it. please anybody help. i was using below code in functions.php
add_filter( ‘woocommerce_checkout_fields’ , ‘custom_override_checkout_fields’ );

function custom_override_checkout_fields( $fields ) {
    unset($fields['billing']['billing_first_name']);
    unset($fields['billing']['billing_last_name']);
    unset($fields['billing']['billing_company']);
    unset($fields['billing']['billing_address_1']);
    unset($fields['billing']['billing_address_2']);
    unset($fields['billing']['billing_city']);
    unset($fields['billing']['billing_postcode']);
    
    unset($fields['billing']['billing_state']);
    unset($fields['billing']['billing_phone']);
    
    unset($fields['billing']['billing_address_2']);
    unset($fields['billing']['billing_postcode']);
    unset($fields['billing']['billing_company']);
    unset($fields['billing']['billing_last_name']);
    
    unset($fields['billing']['billing_city']);
    return $fields;
}

and it was working fine before

i also tried using woo checkout manager and other plugins but nothing is hiding billing first name text box.

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