Update,
With this snippet, you can disable the default functionality, of zooming when you focus (click) on an input field in wordpress and woocommderce. It works for all the input fields on your site.
//disable zoom on mobile
function disable_mobile_zoom() {
echo '<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=0">';
}
add_action( 'wp_head', 'disable_mobile_zoom' );