diff --git a/services/token-aggregation/src/api/routes/omnl.ts b/services/token-aggregation/src/api/routes/omnl.ts
index 1ed47e1..22acd28 100644
--- a/services/token-aggregation/src/api/routes/omnl.ts
+++ b/services/token-aggregation/src/api/routes/omnl.ts
@@ -105,7 +105,8 @@ router.get('/omnl/gazette/notices', (_req: Request, res: Response) => {
 });
 
 router.get('/omnl/gazette/notices/:documentId', (req: Request, res: Response) => {
-  const notice = getGuosmmNotice(req.params.documentId);
+  const documentId = String(req.params.documentId ?? '');
+  const notice = getGuosmmNotice(documentId);
   if (!notice) {
     res.status(404).json({ error: 'Notice not found' });
     return;