diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 30d7d85..402927a 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -24,6 +24,7 @@ jobs:
           configuration: phpunit.xml
           php_version: ${{ matrix.php-version }}
           php_extensions: bcmath gmp xdebug
+          version: 9.6.9
   phpcs:
     runs-on: ubuntu-latest