Roland Company, a retail store, has utilized your services as an independent auditor for several years. During the current year, the company opened a new store, and in the course of your annual audit, you verify the cost of the fixtures installed in the new store by examining purchase orders, invoices, and other documents. This audit brings to light an understated invoice nearly a year old in which a clerical error was made by the supplier, Western Showcase. The total of the invoice was incorrectly stated to be $28,893.62 when it should have been $82, 893.62. The invoice was paid in full with no mention of mistake. The difference in the invoice is material to both companies.

What action should you take in this situation if your client declines to take any action in the matter? Are there ethical rules that you should follow?