How do I change the view? I navigate Invoicing->Customer->open specific customer. Usually shows open /paid invoices, unbilled and unapplied payments. Now just a form.

Hi there, @JH66.

It could be that the stored cache and cookies are the reason why the you're unable to see the details in the Transaction List column in the Customers window.

Let me share some basic troubleshooting steps that will help you get back to work. Let's start by accessing your QBO account using a private browser. This doesn't save your site data and visited pages. Here'how:
 

• Press Ctrl + Shift + N for Google Chrome.
• Ctrl + Shift + P for Mozilla Firefox.
• Control + Option + P (Safari).

If you're able to view the details and status of your customer's transactions again, let's go back to your regular browser and clear the cache to delete the junk files. If the same thing happens, we can use other supported browsers for the meantime so you can get to your tasks. The one you're currently using may have temporary issues with QuickBooks.
 

In addition, you can run the Invoices and Receive Payments report in QuickBooks Online (QBO). This will show you the list of payments that you've received and the invoices that go with them. Go to Reports and look for the Invoices and Receive Payments report.

 
I'm always here to help if you have any other concerns or questions. Just tag my name in the comment section and I'll get back to you as soon as I can. Have a great day and stay safe.