diff --git a/epdb/legacy_api.py b/epdb/legacy_api.py
index 3600f549..d2153a6e 100644
--- a/epdb/legacy_api.py
+++ b/epdb/legacy_api.py
@@ -1970,7 +1970,7 @@ def add_pathway_edge(request, package_uuid, pathway_uuid, e: Form[CreateEdge]):
 
         if e.multistep and e.multistep.strip() == "true":
             reaction = new_e.edge_label
-            reaction.multistep = True
+            reaction.multi_step = True
             reaction.save()
 
         # Update depths as sideeffect of above operation