diff --git a/.changeset/good-flowers-promise.md b/.changeset/good-flowers-promise.md
new file mode 100644
index 0000000000..659c1ab48e
--- /dev/null
+++ b/.changeset/good-flowers-promise.md
@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-techdocs-backend': patch
+---
+
+Modified response when catalog entity isn't found to resolve issue where `/sync` endpoint was continuously called
diff --git a/plugins/techdocs-backend/src/service/router.ts b/plugins/techdocs-backend/src/service/router.ts
index b99579e0eb..4d5ba0ebf3 100644
--- a/plugins/techdocs-backend/src/service/router.ts
+++ b/plugins/techdocs-backend/src/service/router.ts
@@ -242,14 +242,14 @@ export async function createRouter(
       targetPluginId: 'catalog',
     });
 
-    const entity = await entityLoader.load({ kind, namespace, name }, token);
-
-    if (!entity?.metadata?.uid) {
-      throw new NotFoundError('Entity metadata UID missing');
-    }
-
     const responseHandler: DocsSynchronizerSyncOpts = createEventStream(res);
 
+    const entity = await entityLoader.load({ kind, namespace, name }, token);
+    if (!entity?.metadata?.uid) {
+      responseHandler.error(new NotFoundError('Entity metadata UID missing'));
+      return;
+    }
+
     // By default, techdocs-backend will only try to build documentation for an entity if techdocs.builder is set to
     // 'local'. If set to 'external', it will assume that an external process (e.g. CI/CD pipeline
     // of the repository) is responsible for building and publishing documentation to the storage provider.