Hello there, Forkan Uddin1.
There are troubleshooting steps we can try on to get rid of the error. Unexpected errors in QBO are usually caused by the stored files in our browser that can affect browsing performance.
As Fiat Lux - ASIA suggestion, we can try logging in to an incognito window to determine if it's a browser-related issue. If you haven't tried it yet, you can follow the shortcut keys below, depending on what browser you're using:
- Google Chrome: Ctrl + Shift + N
- Microsoft Edge: Ctrl + Shift + P
- Firefox: Ctrl + Shift + P
- Safari: Command + Shift + N
If the error won't appear, we can go back to our main browser and clear the cache. This is to start your data fresh and help QuickBooks to work well. Lastly, you can use other supported browsers like Mozilla, Google Chrome, Microsoft Edge, and Safari. For Safari, make sure to use the latest one.
Comment again if you have follow-up questions. I'm here to help. Take care and stay safe!