Question: Someone used my old address to obtain a T-Mobile phone account in my name.

I found out because the postman for my old address tipped me off, so I contacted T-Mobile and stopped the account. Then I got a letter from a debt collection agency demanding £400 for cancelling the account.

I again phoned T-Mobile, which cancelled the bill and the debt collection action. It also apologised.

But then I had a letter from the Co-operative Bank, reducing my credit card limit from £7,700 to £1,200. I asked why and was told there was an adverse credit reference, relating to the £400 debt.

The Co-operative Bank then agreed to reinstate my credit limit - subject to me contacting the credit reference agency to have the adverse reference deleted.

Yet T-Mobile says it has removed this already.

For 20 years, I have always paid my credit card bill on time. I don't see why I have to correct the errors of other people when I have been the victim of fraud.

- CW

Answer: T-Mobile insists that it closed the fraudulent account and removed the adverse entry on your credit reference as soon as you made it aware of the fraud.

A spokeswoman says: "For people who believe they have had an account set up fraudulently in their name, we have a dedicated team who will investigate and close it quickly if it is found to be fraudulent. They will also prevent any further billing within a matter of days."

Despite this, some weeks later the adverse entry was still showing on your credit reference file, said the Co-operative Bank. It confirms that the reduction to your permitted credit limit was the result of the adverse entry lodged by T-Mobile.

The bank adds: "As the default marker was placed on to (the reader's) credit file by T-Mobile there is a chance that the next time we, or any other of (the reader's) financial account providers, make an assessment, that his credit limits may be affected as the marker is still active ... we do not have the authority to remove the marker from his file held with (credit reference agency) Experian as it was not put there by us. Only T-Mobile can remove the marker."

Where this is not done properly, the bank advises consumers to complain to the Information Commissioner.

The three UK credit reference agencies have established a shared process to support victims with credit reference problems relating to frauds. This can be accessed through the agencies - in the case of Experian, by emailing identityfraud@ uk.experian.com.

Experian insists that responsibility for the accuracy of data provided to it lies with the supplier - n your case, T-Mobile.

None of this explains why the Co-operative Bank told us that when it checked your credit reference in January the adverse marker was still showing, yet T-Mobile told us on January 5 that it had removed this when notified of the fraud in December.

We are assured that the adverse entry has now been removed.