Scottish Power sent all my bills/statements to their own head office for over a year! It got messed up when I agreed to pay direct debit in 2008. They had broken the law by not providing me with these statements and also, they could not tell me who in the head office was receiving my statements and why they hadn't been forwarded.
I stayed very calm throughout all phone conversations, argued with Spock-like logic...
Result. Got a back dated price fix for 2 years at a low rate before the big price hikes kicked in.
I am now well in credit and planning a holiday to Blackpool, possibly Southport.