diff --git a/client/src/app/core/repositories/agenda/item-repository.service.ts b/client/src/app/core/repositories/agenda/item-repository.service.ts
index 2671f7ca9..155557ed7 100644
--- a/client/src/app/core/repositories/agenda/item-repository.service.ts
+++ b/client/src/app/core/repositories/agenda/item-repository.service.ts
@@ -139,6 +139,27 @@ export class ItemRepositoryService extends BaseHasContentObjectRepository<
         await this.httpService.delete(restUrl);
     }
 
+    /**
+     * TODO: Copied from BaseRepository and added the cloned model to write back the
+     * item_number correctly. This must be reversed with #4738 (indroduced with #4639)
+     *
+     * Saves the (full) update to an existing model. So called "update"-function
+     * Provides a default procedure, but can be overwritten if required
+     *
+     * @param update the update that should be created
+     * @param viewModel the view model that the update is based on
+     */
+    public async update(update: Partial<Item>, viewModel: ViewItem): Promise<void> {
+        const sendUpdate = new this.baseModelCtor();
+        sendUpdate.patchValues(viewModel.getModel());
+        sendUpdate.patchValues(update);
+
+        const clone = JSON.parse(JSON.stringify(sendUpdate));
+        clone.item_number = clone._itemNumber;
+        const restPath = `/rest/${sendUpdate.collectionString}/${sendUpdate.id}/`;
+        return await this.httpService.put(restPath, clone);
+    }
+
     /**
      * Get agenda visibility from the config
      *
diff --git a/client/src/app/site/agenda/components/list-of-speakers/list-of-speakers.component.ts b/client/src/app/site/agenda/components/list-of-speakers/list-of-speakers.component.ts
index 06f2ac466..d56dcf083 100644
--- a/client/src/app/site/agenda/components/list-of-speakers/list-of-speakers.component.ts
+++ b/client/src/app/site/agenda/components/list-of-speakers/list-of-speakers.component.ts
@@ -440,7 +440,7 @@ export class ListOfSpeakersComponent extends BaseViewComponent implements OnInit
         if (!this.speakers || !this.speakers.length) {
             this.filteredUsers.next(users);
         } else {
-            this.filteredUsers.next(users.filter(u => !this.speakers.some(speaker => speaker.user.id === u.id)));
+            this.filteredUsers.next(users.filter(u => !this.speakers.some(speaker => speaker.userId === u.id)));
         }
     }
 }