diff --git a/.github/workflows/workflow.yml b/.github/workflows/workflow.yml
index 3797c53..35dd948 100644
--- a/.github/workflows/workflow.yml
+++ b/.github/workflows/workflow.yml
@@ -163,9 +163,9 @@ jobs:
         run: __tests__/verify-dotnet.ps1 3.1 2.2
 
   test-proxy:
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-20.04
     container:
-      image: ubuntu:latest
+      image: ubuntu:20.04
       options: --dns 127.0.0.1
     services:
       squid-proxy: