diff --git a/src/secrets_engine/evidence.py b/src/secrets_engine/evidence.py
index eca1eaf..d432d8a 100644
--- a/src/secrets_engine/evidence.py
+++ b/src/secrets_engine/evidence.py
@@ -100,7 +100,7 @@ class EvidenceWriter:
             "author": self.author,
         }
         if self.workstream_id:
-            payload["workstream_id"] = self.workstream_id
+            payload["workplan_id"] = self.workstream_id
         if decision_id:
             payload["detail"] = {"decision_id": decision_id, "catalog_id": catalog_id}
         try: