I'll share insight on how you can deal with this situation.
The first thing to check is the QuickBooks Online (QBO) company you're logged in to. Ensure it's the correct company and isn't something else. Otherwise, check the Audit Log to view changes made to the QBO company.
Go to the Gear icon.
Select Audit log.
You can also open your browser's private window. It will allow you to isolate the browser's cache, which is a common cause of unexpected issues for browsers.
Google Chrome: Ctrl + Shift + N
Microsoft Edge: Ctrl + Shift + P
Firefox: Ctrl + Shift + P
Safari: Command + Shift + N
If it works, go back to your regular browser and clear its cache. In case it persists, open an alternative browser available for you.
Should you encounter other browser-related issues, you can refer to this article: Troubleshooting browser problems. It has a list of troubleshooting steps specific for all browsers compatible with QBO.
Don't hesitate to place a comment below if you need further assistance. I'll take care of it.