Hi @S_J_MITRA, This behaviour is expected for commodity options. In commodities like Natural Gas, options are priced with reference to the near-month futures contract, not the option’s own expiry month future. In your example, even though you are building a strategy for NG Jan 26 options, the December futures price is used because it is the nearest active futures contract until it expires on 26 December 2025.
Once the December futures expire, the system will automatically shift to using the January futures as the reference price.