We have cheked this issue at our end it seems everything is working fine here, most probably this error accur due to the data is not available between that date range. Could you please share the more details like Game name API Key and Secret Key on support (email@example.com)? It will help us to provide better support to you from our end.
Note : It will return max 30 days data prior to the end date. Also, the data which will get returned will not be in real time, there will be a lag of few hours.u