EXPEDIA TRAVEL - EXPEDIA.COM Glitching system gave us tickets on the wrong day Internet

I ordered tickets for Cirque du Soleil's Ka through expedia along with flight and hotel accommodations.  I am scheduled to arrive in Vegas on the 22nd of May, 2010 around five thirty pm.  The tickets that I purchased for Ka were supposed to be for the 26th of May, which is a Wednesday.  However, the tickets that they reserved for me were for the 22nd at 7pm.  It's obvious that there's no way I have the time to get from the airport, to my hotel, and then to the show by 7pm and I'd have never ordered tickets on the day I was arriving.  Somewhere, something got screwed up.

I called to get them changed or canceled, but all I was told was that they don't refund or cancel these kinds of shows.  They didn't seem to get the point that I wouldn't have had to call to ask them to fix the problem if they hadn't made the mistake in the first place.  Those tickets aren't cheap and this is the first vacation I have been able to afford to take in about six years.  I want my money back as I have already gotten the right tickets from somewhere else after their refusal to simply give me the right night for my tickets.