SESSION_NOT_FOUND in EXECUTE_TRANSACTION Android

[Etaliya]

{"error_code": "SESSION_NOT_FOUND", "error_info": {}, "error_message": "The device doesn't has any active session. Please authorize a session before doing any transaction. Workflow details provided at https://dev.ost.com/platform/docs/sdk/references ", "internal_error_code": "km_ts_st_2", "is_api_error": 0}

I have authorize my android device and trying to execute transaction but it throw error.
it's working in iOS but not in android.