The following error is shown after click the link to confirm:
Fatal error: Uncaught Exception: DateTimeZone::__construct(): Unknown or bad timezone () in /home1/lijhs743/public_html/wp-content/plugins/easy-appointments-connect/src/icalendar_logic.php:173 Stack trace: #0 /home1/lijhs743/public_html/wp-content/plugins/easy-appointments-connect/src/icalendar_logic.php(173): DateTimeZone->__construct('') #1 /home1/lijhs743/public_html/wp-content/plugins/easy-appointments-connect/src/icalendar_logic.php(94): EAC_ICalendar_Logic->create_ics(Array, 'Cita.ics') #2 /home1/lijhs743/public_html/wp-includes/class-wp-hook.php(286): EAC_ICalendar_Logic->process_notification(Array, Array) #3 /home1/lijhs743/public_html/wp-includes/plugin.php(203): WP_Hook->apply_filters(Array, Array) #4 /home1/lijhs743/public_html/wp-content/plugins/easy-appointments/src/mail.php(509): apply_filters('ea_user_mail_at...', Array, Array) #5 /home1/lijhs743/public_html/wp-content/plugins/easy-appointments/src/mail.php(203): EAMail->send_status_change_mail('4') #6 /home1/lijhs743/public_html/wp-includes/class-wp-hook.p in /home1/lijhs743/public_html/wp-content/plugins/easy-appointments-connect/src/icalendar_logic.php on line 173