There seems to be some issue with the master list https://margincalculator.angelbroking.com/OpenAPI_File/files/OpenAPIScripMaster.json
Till Friday symbols - "NATURALGAS24OCTFUT" and "SILVERM24NOVFUT" were tagged to exchange as "MCX". Today they are tagged to exchange as "NCO" which is not defined at https://smartapi.angelbroking.com/docs/Historical under exchange constants. I can get data for NSE but not for these tickers. The lot size is also incorrect for most of the MCX tickers. In the screenshot below, it should be 1250.
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