american express charged me for charges i did not authorize

back in october 2000 i attempted to buy an plane ticket from onetravel.com when i did not get a confirmation i called them to see if i got the ticket i was told no, i called ameican express and was told there were to charges. i then called onetrave.com and american express again before buying another ticket. which i did get confirmation and an email from one travel. i then got my bill from american express showing a charge for a twa flight and an us airways fligt. i knew about the us airway flight but i had thought i did not get the twa flight and after checking with amxpress twice and onetravel as well as emailing onetravel,i got the us airway flight. i disputed it w/american express but they did not dispute it with the right company they went directly to twa i had already checked with twa and was told had i bought it thru them they could do a refund but since i bought it from onetravel, american express would have to dispute w/them. i told american xpress but they won't lissen to me and now are charging me for a ticket i did not allow to be charged to my credit card.
nor have they disputed it like they should have.