diff --git a/.github/workflows/update-version.yml b/.github/workflows/update-version.yml
index d32627e72..3c450f8d1 100644
--- a/.github/workflows/update-version.yml
+++ b/.github/workflows/update-version.yml
@@ -32,8 +32,8 @@ jobs:
         with:
           install_url: https://releases.nixos.org/nix/nix-2.13.3/install
           extra_nix_config: |
-            substituters = http://cache.nixos.org https://hydra.iohk.io
-            trusted-public-keys = cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY= hydra.iohk.io:f/Ea+s+dFdN+3Y/G+FDgSq+a5NEWhJGzdjvKNGv0/EQ=
+            substituters = http://cache.nixos.org
+            trusted-public-keys = cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY=
       - name: 'Update pyk release tag'
         run: |
           K_VERSION=$(cat deps/k_release)