I have one of these at the moment, virtually the same circumstances - request to cancel was sent midday on the 16th January, but it still says awaiting buyer's response, and the eBay help page says it has to be closed manually if the buyer doesn't respond after 7 days, and that you have to close it before 60 days from date of sale. (Mine's been 7 days since the request was sent, by my calculation, but I don't have an option to close yet).