It is bad. I am aware that some meters have duplicated reference numbers; because someone keyed in a wrong digit, and you can be stuck with your existing supplier because they think you are trying to change the address of a meter at another property.

I was stuck paying a high tariff in Shetland when this happened and even sending them a photo of the meter with that days newspaper wouldn't convince that it was my meter. In the end in had to switch to Scottish power as they owned the meter. Apparently the duplicated meter was somewhere in the South of England