I hope you're having a great week so far. To give you the best solution, what's causing you to be locked out of your account? (Examples: Error messages, incorrect credentials, etc.) If you're receiving an error message, let's try to clear your browsing data. This will allow you to log into QuickBooks without messages or glitches standing in your way. Here's on how:
Go to the Three Vertical Dots in the top right-hand corner of the browser.
Choose History and then History again.
Press Clear Browsing Data on the left-hand side of the screen.
Select All Time in the "Time Range" drop-down box.
Click Clear Data.
That's it! Afterward, try logging back into your account. If you're using a different browser, here's a link that can give you the details on how to clear file data within your browser.
Touch base with me after trying these steps, and let me know how it goes. I'll be waiting for your response.