Please go to theme directory help/libs/metaboxes/views/js and open map.js


Replace 


$('#event_start_time, #event_end_time').datetimepicker({timeFormat: 'hh:mm:ss', dateFormat: 'yy-mm-dd'}); line


to


$('#event_start_time, #event_end_time').datetimepicker({timeFormat: 'HH:mm:ss', dateFormat: 'yy-mm-dd'});


at line number 62.