If you have used the service and do not dispute the amount of this provision, then you cannot rely on your ignorance of the charges involved as a reliable defence to avoid paying for the service that has been provided, for which you have entered into a contract.

Under the circumstances you would be better off trying to negotiate a substantially reduced repayable amount, on the strict written understanding it's accepted as a full and final settlement.

Hi there

I just returned from an ash-enforced two and a half week stay in Saudi Arabia. Wary of the hotel charges for internet, I used my 02 dongle. On my return, I was presented with a GBP7,700 bill! Obviously, I challenged this and the O2 rep said simply that "it is up to the customer to check the rates" before use. She seemed to imply that I should have known that it would cost that much. I'm new to dongles and simply had no idea it would cost that much... if I did, why on earth would I continue and rack up a 7.5k bill??

Any suggestions about how to proceed with them?

Many thanks