Just found this problem my self. Worse I have been using it for a few bits and pices in the last few months, after a period when i probably didn't use it much. I've just found out though, having phoned for a replacement card as the current one literally disintegrated with age, that the account was locked. Anything I should have been credited with over the last many months has gone. But I might get my old points back, if they feel generous.
But you'd have expected some shop to have said the card wasn't valid
