Getting "No LTP data available for NSE_FO|61668. Verify instrument key or market hours"

I checked the instrument key from “https://assets.upstox.com/market-quote/instruments/exchange/complete.csv.gz” and tried during market hours. I tried with other instrument keys as well, but always get similar error message.
I have imported upstox_client , ApiException and am using the upstox_client.MarketQuoteApi and get_full_market_quote methods.

Please suggest where I am going wrong?

Thanks