Customer terms field does not populate in invoices that are uploaded through an api

It's good to have you here in the Community, Bobal.

Let's direct you to the right support team that handles your concerns regarding application integration in QuickBooks Online.

I'd suggest reaching out to our Developer Support for assistance in mapping the customer field in Invoices via the API.

To do so:
 

1. Go to the Developer Support page.
2. Choose QuickBooks Online.
3. Hit Ask a Question.

I've got you this helpful article with updates from our developers: Developer Support Blog.

Let me know in the comments if you have additional questions about your invoices within QuickBooks. The Community is always here to help you.