Left British Gas for another supplier, they owed me money when I left which they promised to send a cheque for. They failed to do so! I contact support and they said they would fix the problem and get a cheque sent out ASAP .... again months go by and nothing. I have filled in 2 complaints forms and never got a reply about the money they still owe me to this day. After contacting Citizens Advice they said to get a deadlock letter from British gas to make a formal complaint with the energy Ombusdman, currently they still have not replied to my request and still owe me money. You can bet if I owed them money they would be sending collection agents to get it! Terrible customer service and illegal business practices.