Thanks for sharing the prompt message you received on your end, @peekaboo.
I’m here to help and ensure you’ll be able to log in to your QuickBooks Online (QBO) account.
To clarify we’re on the same, are you the Master Admin of the QBO account? If not, then I’d recommend getting in touch with the Master Admin and verify if they granted you the access to open their account.
However, if you’re the Master Admin and you’re unable to access your account. I suggest reaching out to our support team. There, they’ll add you to the list of affected users and be notified via email of any updates.
You can also refer to this article for more details: QuickBooks Online Support.
Once everything is settled, you might want to check these links for additional reference in setting up a new company in QBO and how to switch between them:
Leave a message reply below if there’s anything else I can help you in managing your QBO accounts. I’ll be around ready to back you up. Keep safe.