Happened to me in 2007, they took 750 GBP from my back account. I complained, it was never explained what happened. They paid the money back to me over a period

Happened to me in 2007, they took 750 GBP from my back account. I complained, it was never explained what happened. They paid the money back to me over a period of about 4 months. It was utterly ridiculous.