diff --git a/.github/workflows/sign.yml b/.github/workflows/sign.yml
index 0ebb261..af4dffa 100644
--- a/.github/workflows/sign.yml
+++ b/.github/workflows/sign.yml
@@ -17,7 +17,9 @@ permissions:
 
 jobs:
   sign:
-    if: ${{ github.event.workflow_run.conclusion == 'success' }}
+    if: >
+      (github.event_name == 'workflow_run' && github.event.workflow_run.conclusion == 'success')
+      || github.event_name == 'workflow_dispatch'
     runs-on: ubuntu-latest
 
     steps: