Hi kszpirak, 

Multi-Factor Authentication is a great way to keep your information secure.  Having a unique one-time passcode is beneficial for verifying your identity with a one time code sent directly to your device.  To ensure you're able to connect, it's important to update your credentials in QuickBooks, so they match with your login information when accessing your bank's website.  

Follow these steps to review and edit your bank sign-in info, in QuickBooks Online;

1. From the left menu, open Transactions, then Bank transactions

2. Click on the Edit  on the blue tile for the bank account

3. Select Edit sign in info

4. Enter the sign in credentials exactly as you would when logging in on your bank's website

5. When ready, hit Connect.

Let us know if you have any other questions.  We are always glad to help!