You will find it is actually the Utility company which is at fault. In simple terms when the old account is closed a marker is put onto that account to divert all payments( in and out) to the new bank. However, some utilities when instructed of a switch, cancel the original direct debit and create a new one, then fail to set it up properly with the new bank . I would shout at the utility company in the first instance ( because that is what the bank will tell you to do). If that fails, speak to the new bank and ask them for proof that the utility company was instructed.