I keep getting a bad request every time i try to login

Hello there, Nadia. I'll ensure to help you log in to your QuickBooks Self-Employed (QBSE) account.

You may have logged on to the account with the incorrect link. We need to make sure to log in to the correct QBSE link. Having the incorrect login page can be the reason for the issue.

Otherwise, I'd recommend logging in the private window. The private window will not save your browsing history, cookies, site data, or information entered. 

You can use either of these shortcut keys:

• Press Ctrl + Shift + N (Google Chrome or Edge).
• Press Ctrl + Shift + P (Mozilla Firefox).
• Press Command + Shift + N (Safari).

If this works fine from there, we can switch back to your regular browser and clear its cache. If the issue persists, you can use other supported browsers to narrow down the cause.

Moreover, you might want to visit this article to learn how to access your Intuit Account and download your personal data: Access and manage your personal data from your Intuit Account.

You're always welcome to reply in the comments if you require further assistance managing your credentials in QBSE. I'll keep an eye out for it. Stay safe.