diff --git a/src/backend/middlewares/thumbnail/ThumbnailGeneratorMWs.ts b/src/backend/middlewares/thumbnail/ThumbnailGeneratorMWs.ts
index 136564ca..050444a8 100644
--- a/src/backend/middlewares/thumbnail/ThumbnailGeneratorMWs.ts
+++ b/src/backend/middlewares/thumbnail/ThumbnailGeneratorMWs.ts
@@ -74,6 +74,7 @@ export class ThumbnailGeneratorMWs {
       for (const item of persons) {
         erroredItem = item;
         if (!item.sampleRegion) {
+          item.missingThumbnail = true;
           continue;
         }
         // load parameters