REST api: updatedatasources is no more working ?

I have tried an rest api to update datasource of a Dataset as

https://api.powerbi.com/v1.0/myorg/groups/".$group_id."/datasets/".$updated_dataset_id."/updatedatasources

But my bad that the result provides an error. i have even tried for Default.UpdateDatasources, but results the same ?

Please anybody is getting success in updating Direct Query Dataset ? Let me know your sample.. Thanks in advance.