diff --git a/.github/workflows/pr-validation.yaml b/.github/workflows/pr-validation.yaml
index 0157aed..e738305 100644
--- a/.github/workflows/pr-validation.yaml
+++ b/.github/workflows/pr-validation.yaml
@@ -11,6 +11,8 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v4
+        with:
+          fetch-depth: 0  # Fetch all history for all branches
 
       - name: Set up Helm
         uses: azure/setup-helm@v4
@@ -18,6 +20,7 @@ jobs:
       - name: Identify Changed Charts
         id: changed_charts
         run: |
+          git fetch origin ${{ github.base_ref }}
           CHANGED_CHARTS=$(git diff --name-only origin/${{ github.base_ref }} --diff-filter=ACDMRT | grep '^charts/' | awk -F/ '{print $2}' | uniq | tr '\n' ' ')
           echo "CHANGED_CHARTS=$CHANGED_CHARTS" >> $GITHUB_ENV