The availabilities generation must take into concern events that belong in the past but end at some time in the future.

src/application/controllers/Appointments.php

@@ -789,11 +789,8 @@ class Appointments extends CI_Controller {
 
         $provider_appointments = $this->appointments_model->get_batch([
             'id_users_provider' => $provider_id,
-            'DATE(start_datetime)' => $selected_date
         ]);
 
-        $service = $this->services_model->get_row($service_id);
-
         // Sometimes it might be necessary to not take into account some appointment records in order to display what
         // the providers' available time periods would be without them.
         foreach ($excluded_appointment_ids as $excluded_appointment_id)