Hey there, bruce.
That's a good one. I'll be delighted to discuss with you the difference between a Paid and Closed status on an invoice.
When the status of the invoice is Paid, this means that the customer paid the partial amount and there's still an open balance left. On the other hand, when it's Closed, it means that the invoice is paid in full.
For more details about e-invoicing, you can check out this article: Use e-Invoice.
If you have any further questions, please let me know. Thanks for dropping by.