diff --git a/.github/workflows/prompty-python.yml b/.github/workflows/prompty-python.yml
index 3cd3255..b8c9d7b 100644
--- a/.github/workflows/prompty-python.yml
+++ b/.github/workflows/prompty-python.yml
@@ -52,12 +52,12 @@ jobs:
     steps:
       - uses: pdm-project/setup-pdm@v4
         with:
-          python-version: 3.11.5
+          python-version: 3.9
 
       - name: install dependencies
         working-directory: ./runtime/prompty
         run: pdm install
-        
+
       - name: Publish package distributions to PyPI
         working-directory: ./runtime/prompty
         run: pdm publish