This is a really interesting question that the FCRA does not answer. There are two ways to approach this. One is the customer service approach that you describe so that the customer would be aware of the problem. The other way of looking at this is to apply the information correction process. Just as you would if the consumer filed with you or the credit bureau claiming that information was incorrect, you would investigate, correct, and re-report the corrected information. In this situation, you self-discovered the error and corrected it. Under FCRA, it would appear that the rest is up to the credit bureau.