Thanks for reaching out to the Community forum, Louise Henderson.
The Dashboard in QuickBooks Online (QBO) will display an overview of your company and giving you a quick business update in amount values.
On your client's case, I recommend them to use a private browser. This is to verify if this is caused by the system or their browser.
Have them use the keyboard shortcuts below:
- Chrome: Ctrl+Shift+N
- Internet Explorer: Ctrl+Shift+P
- Firefox: Ctrl+Shift+
- Safari: Command+Shift+N
Once done, try to check the values on the Dashboard again. Check to see if it works. If they are, then the main browser may have too much historical data from previously visited websites which slows down internal processes and causes this kind of behavior.
To ensure this doesn't happen again, it's a good idea to clear the cache of the browser they're using. The following article contains the additional insight, as well as steps for the supported browsers: Clear cache and cookies to fix issues when using QuickBooks Online.
Please let me know how it goes. I'll be looking forward to hearing back from you. Have a great day!