Current price is around $2000 ow and $3400 rt. Your itinerary is probably repricing because there is virtually zero I availability on GMP-HND and vv, right now even with a stopover. I think that is partially because JL currently has a 737 scheduled on the route in the Winter schedule.

To keep the fare, you have to downgrade to Y on those segments but it is very hard to get any of the booking options to display that.