So I have a trip coming up in First that was booked a couple of months ago. It cost an arm an a leg when booked, but after getting over the initial shock, I wouldn't have given it another thought.

However, it turns out I will need to make a change on inbound and need to return 1 day earlier than my existing reservation.

When I looked into making the change online, it asked for an additional payment of approximately 1,600 CHF. But if I were to buy a fresh ticket for the new date I want to travel, the fare is about 1,100 CHF less than what I already paid!

Does anyone have any suggestions on what the least painful resolution will be? I want to avoid calling them as far as possible, so maybe one of you folks have some experience with this sort of thing. For a small amount, I wouldn't have made a fuss, but this is effectively a difference of about 2,500 CHF!

My original ticket is on a First Flex fare.