Welcome to the Community, @user28944.
Let me help you sort things out.
The stored cache for a long period causes unusual behavior to the browser. You're possibly experiencing a browser-related issue. To verify, let's try some basic troubleshooting procedures.
Let's log in to your QuickBooks Online company using an incognito page. Here are the keyboard shortcuts in opening a private/incognito window:
If you're able to proceed with your work, you'll have to regularly clear the cache browser.
Just hit the Reply button if you have further questions. Have a nice day!