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No, I'm ashamed to say that I didn't notice that I'd not had a statement in two and a half years, but then with two young kids, a full-time job and half a tonne of post coming through the door every day, I (think), I can be excused!
The accounts were definitely in sole names, we each had our own clubcard number. I'm just writing to Tesco now asking them how this has happened and if they'll consider reimbursing me with any points earned on my card since January 2005. They might not, but it's worth a try.