Go here Amazon.co.uk Help: Help & Customer ServiceI wish that I could, but it seems nigh on impossible these days.
At the bottom of the help list, see 'need more help', click on that and in the next column 'contact us' in the middle of the list ...that will take you to log in and you'll be able to click on orders, click on 'an order I paced' and get it to load more orders. Locate the order for the Karcher and take it from there.
Needless to say i made a hasty journey back home.