Reorder Woo Checkout Fields

I want to make it so that the email field appears first and has priority over first name. How can this be done? I used the following code:

function js_sort_checkout_fields( $fields ) {
$fields[‘billing’][‘billing_email’][‘priority’] = 5;
$fields[‘billing’][‘billing_first_name’][‘priority’] = 15;

return $fields;
}
add_filter( ‘woocommerce_checkout_fields’, ‘js_sort_checkout_fields’ );

TIA 🙂