Unexpected issues in QuickBooks Online can be brought about by problems in the web pages. Have you tried opening your account in a private window? This page prevents cookies from being stored on your computer, making it a great place to identify browser problems.
Use any of these keyboard shortcuts depending on the browser you're using:
Google Chrome: press Ctrl + Shift + N
Mozilla Firefox: press Ctrl + Shift + P
Safari: press Command + Shift + N
However, if you already tried this and still getting the same error when editing payments, I highly recommend contacting our Support Team. You can report the problem to our representatives so they create an investigation under your account. Our engineers can run some diagnostics to fix the problem as soon as possible.
Here's how to get Support:
Click the (?) Help menu at the top right section of your QBO Dashboard.
Tap the Contact us button.
Let me know the result once you've tried the steps. I want to make sure you're able to work with QuickBooks without any issues. If this requires additional help, I'd be happy to help at any time. Have a lovely week ahead!