BES Utilities — overcharged with no proof

We took out a contract for gas and electricity with bes after a broker called us a year a go... since then every month they have told us we owe them more and more... we have NEVER had a bill as we "dont exsist" online they have known this but never bothered to do anything? We have spoken privately to a gas expert who suggested that because our meter is old we are been charged in the wrong cubic measurement as even the meter department of bes agreed it's a large amount for a 7 table restaurant with one 6 ring burner and a domestic boiler that's not used for heating? However they have never sent anyone our even after saying they would. We have never been able to see a bill even after they have requested for more money... this company have a terrible reputation and nobody seems to care about the damage they are doing ripping people off...
I have supplied a picture of what happens when we try to get online to provide a reading or get a bill...