'The token supplied to the function is invalid' in ClientContext Update()

[Gamment]

The ClientContext Update() method accepts some 'token'. I presume it should be the one that's returned from NewClientContext() method as 'outputToken'. However, when I do pass the 'outputToken' to the Update() method it throws the 'The token supplied to the function is invalid' error. What would be the correct input 'token' for the Update() method, how should the user prepare such a correct 'token'?