diff --git a/app/Presenters/SchedulePresenter.php b/app/Presenters/SchedulePresenter.php
index d1c7549c..cfc98a5f 100644
--- a/app/Presenters/SchedulePresenter.php
+++ b/app/Presenters/SchedulePresenter.php
@@ -206,11 +206,13 @@ class SchedulePresenter extends BasePresenter implements Arrayable
     /**
      * Formats the completed_at time ready to be used by bootstrap-datetimepicker.
      *
-     * @return string
+     * @return string|void
      */
     public function completed_at_datetimepicker()
     {
-        return $this->dates->make($this->wrappedObject->completed_at)->format('Y-m-d H:i');
+        if ($this->wrappedObject->completed_at !== '0000-00-00 00:00:00') {
+            return $this->dates->make($this->wrappedObject->completed_at)->format('Y-m-d H:i');
+        }
     }
 
     /**