Under customers there is a customer that owes me money, it showes open with a balance. If I click on ot to view details of invoice and payments. Noting happens

I understand the importance of accessing your invoice and payment information, m-moosa. I'm here to assist you in resolving this matter promptly. 

Usually, clicking on Invoice and Payments within the customer section gives you access to its details. To view the invoice, you'll need to select Edit. Once done, click on Receive payment to pay the outstanding balance.

 I've added a screenshot for your reference. 

If you're not seeing these details, we can perform some troubleshooting steps to fix this. There are times when the browser is full of frequently accessed page resources, which causes some errors or unusual responses. 

Let's start accessing your account using a different or private browser. You can use either of these shortcut keys:

• Google Chrome: Ctrl + Shift + N
• Mozilla Firefox: Ctrl + Shift + P
• Microsoft Edge: Ctrl + Shift + P
• Safari: Command + Shift + N

I'm including these articles you may find helpful in the future while working on a task in QuickBooks Online:

• Customise invoices, estimates, and sales receipts in QuickBooks Online.
• Record invoice payments in QuickBooks Online.

  Keep your post coming if you need additional assistance with managing invoices and payments in QuickBooks. I'm always here to help. Have a great day.