David of Broadway wrote:

Mizter T wrote:

Being a scruff is no crime! Perhaps the RPIs thought someone had lent
you their Oyster, as period Travelcards are non-transferable. However
there is no real way they can enforce this unless they look up the
relevent details on the Oyster database and ask you to confirm them -
something I haven't heard ever having happen, though it's technically
possible. (If you were using a borrowed Oyster then I wouldn't recomend
complaining - but it sounds like the card was indeed yours.)

And even that isn't possible if the Oyster card isn't registered
(although IIRC registration is required for Travelcards valid for longer
than a week).

True. Though as you rightly point out, only 7-day Travelcards are
available on an unregistered Oyster card - anything longer and it needs
to be registered.