diff --git a/openhands/app_server/sandbox/remote_sandbox_service.py b/openhands/app_server/sandbox/remote_sandbox_service.py
index ef60724d9a..1606fc81ae 100644
--- a/openhands/app_server/sandbox/remote_sandbox_service.py
+++ b/openhands/app_server/sandbox/remote_sandbox_service.py
@@ -356,7 +356,7 @@ class RemoteSandboxService(SandboxService):
                         StoredRemoteSandbox.id == runtime.get('session_id')
                     )
                     result = await self.db_session.execute(query)
-                    sandbox = result.first()
+                    sandbox = result.scalar_one_or_none()
                     if sandbox is None:
                         raise ValueError('sandbox_not_found')
                     return self._to_sandbox_info(sandbox, runtime)