diff --git a/app/plugins/builtins/ai_assistant/routes.py b/app/plugins/builtins/ai_assistant/routes.py
index 6a2ace4..258982e 100644
--- a/app/plugins/builtins/ai_assistant/routes.py
+++ b/app/plugins/builtins/ai_assistant/routes.py
@@ -578,10 +578,15 @@ async def chat_stream(
     }
 
     async def event_stream():
-        async for chunk in stream_chat(
-            db, session, agent, data.content, user_context, tenant_id
-        ):
-            yield chunk
+        # Use a fresh DB session — the Depends(get_db) session closes after response
+        from app.core.db import get_session_factory
+        factory = get_session_factory()
+        async with factory() as stream_db:
+            await set_tenant_context(stream_db, tenant_id)
+            async for chunk in stream_chat(
+                stream_db, session, agent, data.content, user_context, tenant_id
+            ):
+                yield chunk
         yield "data: [DONE]\n\n"
 
     return StreamingResponse(
diff --git a/app/services/contact_folder_service.py b/app/services/contact_folder_service.py
index 2198d7f..924fd04 100644
--- a/app/services/contact_folder_service.py
+++ b/app/services/contact_folder_service.py
@@ -111,9 +111,9 @@ async def create_folder(
         sort_order=max_order + 1,
     )
     db.add(folder)
+    result = _serialize_folder(folder)
     await db.commit()
-    await db.refresh(folder)
-    return _serialize_folder(folder)
+    return result
 
 
 async def update_folder(
@@ -143,9 +143,9 @@ async def update_folder(
     if "sort_order" in data and data["sort_order"] is not None:
         folder.sort_order = data["sort_order"]
 
+    result = _serialize_folder(folder)
     await db.commit()
-    await db.refresh(folder)
-    return _serialize_folder(folder)
+    return result
 
 
 async def delete_folder(
@@ -195,9 +195,9 @@ async def move_contact(
         raise ValueError("Contact not found")
 
     contact.folder_id = uuid.UUID(folder_id) if folder_id else None
+    result = {"id": str(contact.id), "folder_id": str(contact.folder_id) if contact.folder_id else None}
     await db.commit()
-    await db.refresh(contact)
-    return {"id": str(contact.id), "folder_id": str(contact.folder_id) if contact.folder_id else None}
+    return result
 
 
 async def reorder_folders(