diff --git a/action.yml b/action.yml
index 314255d7..8c0851dd 100644
--- a/action.yml
+++ b/action.yml
@@ -73,6 +73,7 @@ runs:
         if [[ -z $HEAD_SHA ]]; then
           echo "::warning::Unable to determine the head sha: $HEAD_SHA."
           echo "::warning::You seem to be missing `fetch-depth: 0` or `fetch-depth: 2`"
+          exit 1
         else
           echo "Using head sha: $HEAD_SHA..."