Bidded, won at an insanely low price (I had no problem with that) and then never contacted me, even after repeated emails.

This included one that specifically said 'I'm having other people contact me asking me to Santa, but I'm turning them down until I know when and where you want me, as you're the bid winner, so please contact me as soon as is convenient.'

In a later email I said 'Look, if it was meant to be a joke bid and it just went wrong, I don't mind. Just tell me and we'll cancel it, no harm done.'

Never heard a thing.