Welcome and thanks for dropping by the Community, @cecil-everson.
When you connect your bank in QuickBooks Online (QBO) through Online Banking (Bank Feeds), the system automatically downloads the transactions automatically overnight. Some banks don't post transactions until at a later time or the next day.
To verify the messages that you're getting, I highly suggest contacting your financial institution to check and verify who's trying to log into your bank account.
Just in case, I'll add these articles for future reference:
Reach out to me in the comment section below if you have any other concerns or questions, and I'll get back to you as quickly as possible. I'm always here to help. Have a good one!