diff --git a/openslides/topics/static/js/topics/site.js b/openslides/topics/static/js/topics/site.js
index 4be30afef..e8ddc1929 100644
--- a/openslides/topics/static/js/topics/site.js
+++ b/openslides/topics/static/js/topics/site.js
@@ -309,7 +309,7 @@ angular.module('OpenSlidesApp.topics.site', ['OpenSlidesApp.topics', 'OpenSlides
                     }
                     item.duration = time;
                 } else {
-                    item.duration = null;
+                    delete item.duration;
                 }
                 // is_hidden
                 if (item.is_hidden) {
diff --git a/openslides/topics/static/templates/topics/topic-import.html b/openslides/topics/static/templates/topics/topic-import.html
index 0e851a982..c454bd929 100644
--- a/openslides/topics/static/templates/topics/topic-import.html
+++ b/openslides/topics/static/templates/topics/topic-import.html
@@ -92,7 +92,7 @@
               </span>
               {{ item.title }}
             <td>{{ item.text | limitTo:80 }}{{ item.text.length > 80 ? '...' : '' }}
-            <td>{{ item.duration | osMinutesToTime }}
+            <td>{{ item.duration ? 'item.duration | osMinutesToTime' : '' }}
             <td>{{ item.comment }}
             <td>{{ item.is_hidden }}
       </table>
@@ -100,7 +100,7 @@
 
     <div class="text-danger">
       <i class="fa fa-exclamation-triangle"></i>
-      {{ itemsWillNMotBeImported }}
+      {{ itemsWillNotBeImported }}
       <translate>topics will be not imported.</translate>
     </div>
     <div>