I'm here to help change the default due date of your invoices in QuickBooks Online (QBO), @Rose0512.

It seems that your preferred invoice terms were set to 30 days. To change it, you can go to the Sales form content menu. Here's how:

1. In your QBO account, click the Gear icon and select Account and Settings.
2. Select Sales from the left menu, then go to the Sales form content section.
3. From the Preferred invoice terms drop-down, select the 7 days terms. If you don't have one, you can click Add new and create a 7 days term.
4. Click Save, then Done.

Once done, QuickBooks will set the due date to 7 days every time you create an invoice. 

I'm adding this article to learn how to manage your payment terms: Set up and manage your payment terms.

You may also want to view all your sales transactions in the future. You can go to the Sales menu and select All Sales. This will give you a great view of the status of sales transactions, open invoices, and paid invoices. 

Don't hesitate to leave a comment below if you have other concerns or follow-up questions about the invoice payment terms. I'll be around to provide further assistance.