Whenever Accounts Receivable statements are being previewed or printed, the Invoice Comment is not showing for the invoice
1. Verify the invoice is not paid. If the invoice is paid, the comment will not show 2. On your statement setup, go to the "Details" tab and look to see if "Invoices and returns" is checked under the "Show transaction details for" heading. If it is checked, this will not show the Invoice, instead it will show the Invoice Line item. Unmark this if you would like to see your invoice comments.