Hi Hove4u,
i’ve changed the file in /woocommerce-checkout-manager/woocommerce-checkout-manager.php from line 384
wp_enqueue_script('jquery-ui-datepicker');
wp_enqueue_style('jquery-style', plugins_url('woocommerce-checkout-manager/includes/pickers/jquery.ui.css') );
// https://fgelinas.com/code/timepicker/
wp_enqueue_script( 'jquery-lib', '//ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js' );
wp_enqueue_script( 'jquery-ui-lib', '//ajax.googleapis.com/ajax/libs/jqueryui/1.11.4/jquery-ui.min.js' );
wp_enqueue_script('jquery-ui-timepicker', plugins_url('woocommerce-checkout-manager/includes/pickers/jquery.ui.timepicker.js') );
wp_enqueue_style('jquery-ui-timepicker', plugins_url('woocommerce-checkout-manager/includes/pickers/jquery.ui.timepicker.css') );
wp_enqueue_style('jquery-ui-timepicker-min', plugins_url('woocommerce-checkout-manager/includes/pickers/include/ui-1.10.0/ui-lightness/jquery-ui-1.10.0.custom.min.css') );
this isn’t a good solution (an update of the plugin will broke my solution.. but for now: it’s work ??