diff --git a/src/blenderbim/blenderbim/bim/module/cost/operator.py b/src/blenderbim/blenderbim/bim/module/cost/operator.py
index 2769e559a4..fe69a2b6d9 100644
--- a/src/blenderbim/blenderbim/bim/module/cost/operator.py
+++ b/src/blenderbim/blenderbim/bim/module/cost/operator.py
@@ -239,6 +239,8 @@ class RemoveCostItem(bpy.types.Operator, tool.Ifc.Operator):
             contracted_cost_items.remove(props.active_cost_item_index)
         props.contracted_cost_items = json.dumps(contracted_cost_items)
         bpy.ops.bim.enable_editing_cost_items(cost_schedule=props.active_cost_schedule_id)
+        if props.active_cost_item_id == self.cost_item:
+            props.active_cost_item_id = 0
         return {"FINISHED"}
 
 
diff --git a/src/blenderbim/blenderbim/core/sequence.py b/src/blenderbim/blenderbim/core/sequence.py
index 4378d2cb96..edd5da5dda 100644
--- a/src/blenderbim/blenderbim/core/sequence.py
+++ b/src/blenderbim/blenderbim/core/sequence.py
@@ -64,7 +64,7 @@ def assign_work_schedule(ifc, sequence, work_plan=None, work_schedule=None):
 
 
 def unassign_work_schedule(ifc, work_plan=None, work_schedule=None):
-    ifc.run("aggregate.unassign_object", relating_object=work_plan, product=work_schedule)
+    ifc.run("aggregate.unassign_object", product=work_schedule)
 
 
 def enable_editing_work_schedule(sequence, work_schedule=None):