diff --git a/backend/src/Squidex.Domain.Apps.Entities.MongoDb/Assets/MongoAssetRepository.cs b/backend/src/Squidex.Domain.Apps.Entities.MongoDb/Assets/MongoAssetRepository.cs
index 379e9d6e2..611c5be9e 100644
--- a/backend/src/Squidex.Domain.Apps.Entities.MongoDb/Assets/MongoAssetRepository.cs
+++ b/backend/src/Squidex.Domain.Apps.Entities.MongoDb/Assets/MongoAssetRepository.cs
@@ -150,7 +150,7 @@ namespace Squidex.Domain.Apps.Entities.MongoDb.Assets
             using (Profiler.TraceMethod<MongoAssetRepository>())
             {
                 var assetEntities =
-                    await Collection.Find(x => x.IndexedAppId == appId && !x.IsDeleted && x.ParentId == parentId).Only(x => x.DocumentId)
+                    await Collection.Find(x => x.IndexedAppId == appId && !x.IsDeleted && x.ParentId == parentId).Only(x => x.Id)
                         .ToListAsync();
 
                 return assetEntities.Select(x => DomainId.Create(x[Fields.AssetId].AsString)).ToList();