On the Oyster Card web site, I get this message:

"Your Oyster card has been stopped and you will not be able to use it
for any transaction on this site. Please call the Oyster Helpline on
0845 330 9876 for further information."

I did lose it - along with my work ID badge - a couple of weeks ago,
but never got around to reporting it. Yes, it had auto top-up on it
and I know I should have cancelled it right away - but I never quite
got around to it.

How else could it have got cancelled? I can only guess that someone
picked it up, and handed it in - but in that case, shouldn't I receive
an email or something saying it was found since it was properly
registered...

Or is there something much cleverer going on?

David.