I can't login online but I can on my app

Since you're able to log into the app, could you please clarify whether you used your email, user ID, or phone credentials? Please note that an email or phone can be associated with multiple user IDs, and different user IDs can have different companies associated.

To check your user ID and the companies associated with your account in the app, go to the Profile icon > Manage your Intuit Account. From there, navigate to Sign in & security to find your user ID, and Products & billing to see the associated companies. Make sure to use the same user ID when logging in online, and ensure you are using the correct login link: https://qbo.intuit.com.

If you have any other concerns, feel free to reply in the comments.