Columbia Gas Unauthorized Switch of Utilities

[Daniel K.]

Columbia Gas in Ohio charged me for my tenant's last month of service by sending me an invoice with a new account number under my name to my home address.  Per my lease, tenants have to put the gas in their name as this was done.  I called them to tell them the forwarding address of my tenant, because for some odd reason they sent his last month's bill to me in my name, and so they said they would send it.  Now I am getting a bill with no payment period listed on it, threatening my credit if I don't pay this bill they said was going to be sent to the tenant.

The tenant of course swears he paid the last month and notes it isn't even his account number on the invoice.  Since I did not authorize new service in my name, can they really let this harm my credit in case they never collect from the tenant?   And if they do, how long would it take them to do it, and by how much and what recourse do I have to resolve it, in case this doesn't get resolved by then (or they say it was resolved again, but didn't like before, you know how this often goes)