diff --git a/renovate.json b/renovate.json
index ce0e09de5..dee312c44 100644
--- a/renovate.json
+++ b/renovate.json
@@ -3,6 +3,12 @@
     "github>dev-hato/renovate-config"
   ],
   "packageRules": [
+    {
+      "matchPackageNames": [
+        "flask"
+      ],
+      "allowedVersions": "<3.0.0"
+    },
     {
       "matchPackageNames": [
         "postgres"