Unfortunately, the taxpayer didn’t receive the CRA’s overcontribution notice because he had not updated his mailing address with the CRA. As an aside, if you move, it’s important to notify the CRA of your change of address, which can be done in a number of ways, including online, by phone, by mail and even when you file your return (but only if you paper file, or you have your return filed electronically through a tax preparer or authorized service provider using EFILE). You cannot change your address when using NETFILE to file your own return.