diff --git a/.github/workflows/cluster-faces-test.yml b/.github/workflows/cluster-faces-test.yml
index 89bf4828..19ddd567 100644
--- a/.github/workflows/cluster-faces-test.yml
+++ b/.github/workflows/cluster-faces-test.yml
@@ -17,7 +17,7 @@ env:
 
 jobs:
   php:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
 
     strategy:
       # do not stop on another job's failure