diff --git a/helpers/ui_server.py b/helpers/ui_server.py
index fdea68b017..a567f2ebdc 100644
--- a/helpers/ui_server.py
+++ b/helpers/ui_server.py
@@ -80,7 +80,7 @@ def create(cls) -> "UiServerRuntime":
         WerkzeugRequest.max_form_memory_size = UPLOAD_LIMIT_BYTES
         webapp.config.update(
             JSON_SORT_KEYS=False,
-            SESSION_COOKIE_NAME="session_" + runtime.get_runtime_id(),
+            SESSION_COOKIE_NAME="session_" + runtime.get_persistent_id(),
             SESSION_COOKIE_SAMESITE="Lax",
             SESSION_PERMANENT=True,
             PERMANENT_SESSION_LIFETIME=timedelta(days=1),