Plugin Install Error

I tried to install the plugin but I got the following errors:

Warning: fopen() [function.fopen]: http:// wrapper is disabled in the server configuration by allow_url_fopen=0 in /home/devpex/public_html/wp-content/plugins/sharetimetable-booking/sharetimetable.php on line 572

Warning: fopen(http://app.sharetimetable.com/api/test//http://apex-closings.com) [function.fopen]: failed to open stream: no suitable wrapper could be found in /home/devpex/public_html/wp-content/plugins/sharetimetable-booking/sharetimetable.php on line 572

Warning: fread() expects parameter 1 to be resource, boolean given in /home/devpex/public_html/wp-content/plugins/sharetimetable-booking/sharetimetable.php on line 573

Fatal error: Uncaught exception 'Exception' with message 'String could not be parsed as XML' in /home/devpex/public_html/wp-content/plugins/sharetimetable-booking/sharetimetable.php:574 Stack trace: #0 /home/devpex/public_html/wp-content/plugins/sharetimetable-booking/sharetimetable.php(574): SimpleXMLElement->__construct('') #1 [internal function]: ShareTimetablePlugIn->optionsPage('') #2 /home/devpex/public_html/wp-includes/plugin.php(525): call_user_func_array(Array, Array) #3 /home/devpex/public_html/wp-admin/admin.php(236): do_action('plugins_page_sh...') #4 /home/devpex/public_html/wp-admin/plugins.php(10): require_once('/home/devpex/pu...') #5 {main} thrown in /home/devpex/public_html/wp-content/plugins/sharetimetable-booking/sharetimetable.php on line 574

https://ww.wp.xz.cn/plugins/sharetimetable-booking/