Have been holding a confirmed e-ticket FLL-ATL-SAN-LAX-JFK, westbound 3/9, eastbound 3/12.

Today, while 'noodling around' in My Itineraries, found that my ATL-SAN flight, 444, was showing 'waitlisted' and now booked on 312 (exactly same itinerary and aircraft, but my seat had disappeared. Looked like just a flight number change) Called SMS.

While on endless hold, to pass time, to look for seating on 'new' 312 a/c, started new, identical reservation, only to find fare was $151 dollars LESS than I'd paid (basically, original seat on ATL-SAN was in Q, but T was now available. When asking for refund (credit) for the fare difference, was told that Delta now charges $50 to reissue ticket at the lower fare, since this is a reticketing!!! Customer care [what a euphemism] spent 30 minutes trying to find the regs governing this, refused to waive the charge.

Do I have any recourse? Anyone in particular in corporate I should contact? The idea of guaranteeing that they will adjust if fares go down, then charge $50 to do so, is simply infuriating! Any and all help welcome.

Thanks