diff --git a/website/src/lib/oasst_api_client.ts b/website/src/lib/oasst_api_client.ts
index 952858f2..7c48a288 100644
--- a/website/src/lib/oasst_api_client.ts
+++ b/website/src/lib/oasst_api_client.ts
@@ -276,7 +276,7 @@ export class OasstApiClient {
    * Returns the counts of all tasks (some might be zero)
    */
   async fetch_available_tasks(user: BackendUserCore, lang: string): Promise<AvailableTasks> {
-    return this.post(`/api/v1/tasks/availability`, { ...user, lang });
+    return this.post(`/api/v1/tasks/availability?lang=${lang}`, user);
   }
 }