I appreciate you reaching out in the Community space, @userjim-keaney.
You can follow these steps for changing the payment terms in your invoice:
- Go to Menu.
- Tap on Invoice.
- Choose the invoice transaction you want to edit.
- Select the Edit ✎ button.
- Edit your payment terms in the Terms section.
- Select Save.
You can also check this article to learn how to record an invoice payment: Receive an invoice payment using the QuickBooks Online mobile app.
Feel free to reply to this post if you have further questions other than changing invoice payment terms. I'd gladly assist you always.