Hi there tpardy,
It's important that all your transactions be entered correctly for your books to be well balanced. QuickBooks Online Accountant is a great tool able to help you manage your client's books from anywhere with an internet connection. I can provide some information about setting up your address.
As stated by Fiat Lux - ASIA, if you have a Canadian accounting firm, you would need to make sure you're using the Canadian site to sign up for QuickBooks Online Accountant. If you are using the US version and are trying to enter a Canadian address, that would be why you'd be receiving the error message.
If you have any other questions, feel free to reach out here.
