To help us narrow down the cause of the error/behavior you've encountered and provide you with the exact resolution, may I know what steps you've done so far and what specific area in QuickBooks you're working with?
If this is a browser and cache related, you may try using the basic troubleshooting steps to resolve the issue. To start with, access your account using an incognito or private browser. You may use these shortcut keys:
Google Chrome, press CTRL+ Shift + N
Mozilla Firefox: press CTRL+ Shift + P
Internet Explorer: press CTRL+ Shift + P
Safari: press Command + Shift + N
If it works successfully using the private browser, access your account using the original browser and clear the browser's cache.
Keep me posted with the result. Wishing you the best!