Purchase Extra Legroom Seating Refund?

I purchased a round trip ticket --- with the additional fee of $138. for extra legroom seating....
United notified of a schedule change involving both flights.
The outbound was not going to work.....so I called and they cancelled the flights...
However --- they would not refund the extra legroom fee (138)....
I understand the non refundable clause (so that you do not change seats on the flight ) but when the entire reservation is cancelled on account of a schedule change by the airline?

Your thoughts are appreciated.
Thanks