That's not true. Just two months ago a friend of mine disputed a DD with her bank and they refused to reverse it because she couldn't prove it was erroneous. I'm nearly sure the DD guarantee used to be stronger, but this part now reads:

> If an error is made in the payment of your Direct Debit, by the organisation or your bank or building society, you are entitled to a full and immediate refund of the amount paid from your bank or building society.