Hello there, sale.
The performance of QuickBooks Online depends on the browser and internet speed. We can troubleshoot it to see if this behavior you're experiencing is just a browser issue.
Let's start by logging in to your QuickBooks using an incognito window. From there, check if you can open your customized forms and company settings.
We can also clear your browser's cache. It's a junk file that causes errors if the browser saves too much of it. In addition, you can access your account through another browser. I suggest Google Chrome, Mozilla Firefox, or Microsoft Edge. Just make sure they are updated.
Keep on posting if you have more questions. I'm always here to help.
