I have has similar problems with southern electric since I moved in to my property two years ago. The only way I got anything resolved was to keep ringing them, which then cost me money on my phone bill. Mine was recalculated from �15 a month to �60 and then I was in credit and they recalculated it to be more! May be you ought to write to them explaining in plain english the situation, then if it gets worse send copies of all your correspondence to the relevant ombudsman. Then hopefully their incompetance will come to light. I feel sorry for the elderly and those who may not be so astute who would just continue to pay, because they are told to do so.