Sell december contract and buy next month contract. Target is above 300
You bought at higher levels.
I dont know which type of trader you are now.
If you are an intraday trader, you should have come out from your position
If you are a positional trader, your stop loss is below 268 only. until it reaches 268, you can hold the position for the target of 300 within 2 weeks.
this is my personal view. take your own decision.
Averaging the position is not advised in these levels