the company in question went to the property after we had given them the final meter reading and confirmed the meter reading and we had a bill for the period ending May this year as a final bill with actual reading, which was paid in full
Friday I received another bill for the same period with another amount on which 8 times the amount and a higher reading by a couple of thousand units 
I cannot get in touch with them because they are closed, but if they insist it isn't a mistake what can I do? I have had this happen before with a different company who eventually agreed it was their mistake after I got the osbudsman involved but I am sick of this crap tbh