I made "sure to add the country in the Country field when setting up the customer," as you said. The problem is the country does not appear ON THE INVOICE. Please advise.
You have the option to customize the template used on your invoices so you can enable and display the country of your customer's address. Let me show you how.
Go to the +New button.
Under CUSTOMERS, select Invoice.
Select Customize.
Choose Edit current.
On the Content tab, select the upper portion of your invoice template.