Let's perform browser troubleshooting steps to bypass this error message, Jojo.
Accumulated cache in your browser can sometimes affect the system's performance. I suggest deleting the cache history so the system can start fresh and to pinpoint any possible issues with the webpage.
We can also explore different supported browser to enhance your experience with QuickBooks Online
For a thorough guide on personalizing and adding specific information to your sales forms and tracking your invoice payments, refer to this article:
If you need any additional help while managing your invoices in QBO, please don’t hesitate to reach out.