I made a reservation for my daughter and I to fly to London from Philadelphia with Expedia on British Air New Year's Day. My daughter is flying onto Madrid after a week and then home to the US, while I am flying home after the week. Expedia separated the intineraries as necessary. However, they booked her ticket in premium economy and mine in regular economy, unbeknownst to me. When I went to the British Air web site to pay for seats in advance to ensure we could sit together, that's when I realized the issue. After several phone calls to both Expedia and British Air, I have been unsuccessful in downgrading my daughter's ticket to regular economy without paying a $275 change fee and difference in fare for the entire ticket which comes to about $1200 (original ticket was $1500). Without the tickets both being in economy class, British Air will not allow seats to be purchased together. Expedia will not change the London leg without all of these charges and claims no responsibility for making the error in the first place. I escalated the Expedia calls to corporate customer service 3 levels ending with Ashley Cross who stated that premium economy must have been the cheapest airfare for the itinerary at that time and that's why it was booked the way it was. Any suggestions on how to get these two companies to work together and allow my daughter and I to sit together?