Sam, a CPA, completed the audit of the financial statements of Supply Inc., a publicly listed company, for the year ended December 31, 2020 and issued an unqualified opinion on February 19, 2021. In July 2021, Sam was at the client's premises to plan for the current year's audit and learned that a material amount of inventory on December 31, 2020 had not been counted nor included in the financial statements because it was on board a ship on that date. The inventory had been shipped from an Asian country and the ownership and risks associated with it had passed to Supply Inc. at the time of shipment. Thus, a liability for payment had properly been included in accounts payable on the December 31, 2020 balance sheet. The client explained that the error was caught in March 2021 but that no adjustment was needed since this error was now "automatically" corrected. Sam agreed with the client and wrote a memorandum on the working papers describing the situation and noting the need to be extra careful in the audit of the client's inventory at the end of the current year. Please discuss whether Sam has violated Code of Professional Conduct, Generally Accepted Auditing Standards, or other standards.