My 9 AM flight UA 922 EWR-LHR departing EWR at 9 AM EST on March 6 (and arriving LHR that night) was cancelled owing to maintenance issues. UA booked me on the next available flight that day, UA 800 departing at 6:05 pm arriving the next day.

Unfortunately I had a hotel reservation in London at the Hilton Metropole (at an non-refundable advance purchase rate). Hilton refused to credit me for the night of the 6th despite my request to do so, as I said it was not my fault. I called immediatelly after the cancellation was announced and also at the time of check-in the next day when I finally arrived. I offered to provide them proof of the airlines' cancellation, to no avail.

Please could someone advise me on how to go about appealing this.

Thanks in advance for any advice.