ONly getting date part of the string.

main/inc/lib/main_api.lib.php

@@ -2012,7 +2012,7 @@ function api_get_session_visibility($session_id, $course_code = null, $ignore_vi
                     $row['date_end'] != '0000-00-00' &&
                     $row['nb_days_access_after_end'] != '0'
                 ) {
-                    $end_date_for_coach = new DateTime($row['date_end'].' 23:59:59');
+                    $end_date_for_coach = new DateTime(substr($row['date_end'], 0 ,10).' 23:59:59');
                     $number_of_days = "P".intval($row['nb_days_access_after_end']).'D';
                     $end_date_for_coach->add(new DateInterval($number_of_days));
 
@@ -2029,7 +2029,7 @@ function api_get_session_visibility($session_id, $course_code = null, $ignore_vi
                     $row['date_start'] != '0000-00-00' &&
                     $row['nb_days_access_before_beginning'] != '0'
                 ) {
-                    $start_date_for_coach = new DateTime($row['date_start'].' 00:00:00');
+                    $start_date_for_coach = new DateTime(substr($row['date_start'], 0, 10).' 00:00:00');
                     $number_of_days = "P".intval($row['nb_days_access_before_beginning']).'D';
                     $start_date_for_coach->sub(new DateInterval($number_of_days));
                     if ($start_date_for_coach->getTimestamp() < $now) {