I appreciate you getting back to us and performing the troubleshooting steps shared by my colleague above, @Salsabil.

Since you're still getting the same error after using Chrome and Internet Explorer via mobile, let's try logging in your QuickBooks Online account through your computer.

You can use these browsers to sign in your QBO account:

• Google Chrome
• Mozilla Firefox
• Safari
• Microsoft Edge

If this works, I suggest changing your Internet Service Provider (ISP) on your mobile phone. This is the possible reason why you can't log in to your QBO account.

If the issue persists, I recommend contacting our Technical Support Team. This way, they can further investigate this matter and provide additional troubleshooting steps to get this fixed.

You can use the QBO test drive so you can reach out to them. And click the Help (?) button at the top right, then select Contact US to connect with a live support agent.

Please know that you can always get back to this post if you have any other questions. The Community team and I are always here to help.