[PHXFlyer]

Getting back on topic, there is no way to equate miles for payment of a fee. You can redeem miles for a ticket, but for fees such as baggage, purchasing beverages or food in-flight, or making itinerary changes one can only use money in the form of cash (if paid at the airport) or a credit/debit card. I think the OP tried to push the "miles instead of a fee" point too many times and was told it couldn't be done which was not what s/he wanted to hear. At some point such conversations become pointless and it was probably at the discretion of the telephone agent to terminate the call.

[Leatherboy2006]

I'd be more upset with my sister then the airline. Some Aunt hopefully she is off the xmas card list.