diff --git a/.github/workflows/merge.yml b/.github/workflows/merge.yml
index 896071e..3ecb281 100644
--- a/.github/workflows/merge.yml
+++ b/.github/workflows/merge.yml
@@ -22,7 +22,7 @@ jobs:
       - name: shallow
         run: cat .git/shallow
       - name: deepend tree
-        run: git fetch --shallow-since "1 year" --tags --recurse-submodules=no
+        run: git fetch --shallow-since "1 year" --tags --recurse-submodules=no --update-shallow
       - name: status
         run: git status
       - name: shallow