We've lived in our house for almost 2 years and up until recently paid our gas bill by direct debit. I had a dispute with BG because they continued to take DD out of my bank account for our previous address which took 18 months to resolve and so I cancelled all DD to them and paid the quarterly bills as I didn't want them having access to my bank account. The other day a man came to read the meter for the first time since we moved in and they've sent me a bill for over £500! We can't pay this (last bill was £135 and we were paying £40 per month on DD before I cancelled it). Is there anything I can do? Help!