My money's on 20 years of bank statements. They're been over your account and found that you owe them £5M in charges and interest on the unpaid charges. You have until 1st Jan 2015 to pay it off or they're coming for your house. And a Happy Christmas card.
Here you go you doubters... A rather pleasant single malt & a pair of Crystal glasses from which to drink it. I CAN HAZ WINNAH
I remember when banks were populated by staff that worked in banks. Now they're populated by staff that worked in Currys/PCWorld.