diff --git a/store/app.py b/store/app.py
index 0f5d6ba7..318558d2 100644
--- a/store/app.py
+++ b/store/app.py
@@ -147,7 +147,7 @@ def app_info(app_id):
 def star_app(app_id, action):
     assert action in ["star", "unstar"]
     if app_id not in get_catalog()["apps"] and app_id not in get_wishlist():
-        return _("App %(app_id) not found", app_id=app_id), 404
+        return _("App %(app_id)s not found", app_id=app_id), 404
     if not session.get("user", {}):
         return (
             _("You must be logged in to be able to star an app")
diff --git a/store/messages.pot b/store/messages.pot
index 081ff592..131eee40 100644
--- a/store/messages.pot
+++ b/store/messages.pot
@@ -8,7 +8,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: PROJECT VERSION\n"
 "Report-Msgid-Bugs-To: EMAIL@ADDRESS\n"
-"POT-Creation-Date: 2024-03-22 04:56+0100\n"
+"POT-Creation-Date: 2024-03-22 04:59+0100\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language-Team: LANGUAGE <LL@li.org>\n"
@@ -18,7 +18,8 @@ msgstr ""
 "Generated-By: Babel 2.14.0\n"
 
 #: app.py:150
-msgid "App %(app_id) not found"
+#, python-format
+msgid "App %(app_id)s not found"
 msgstr ""
 
 #: app.py:153