How do I change my bank account?

I'll assist you in modifying your online bank account in Quickbooks, 549276517.

First, let's disconnect the old bank account and reconnect it using a new bank account.

To disconnect:

1. Tap Banking in the left panel, then Banking.
2. Choose the Edit (pencil icon) on the account you want to change.
3. In the Account window, mark check the Disconnect this account on save box. 
4. Hit Save and Close. 

For further details, click the article below: 

• Disconnect or delete an account from the Downloaded Transactions page

To reconnect the account:

1. Go back to Banking in the left pane, then Banking.
2. On the Banking page, tap Add Account.
3. Search for your financial institution and select it from the list.
4. Enter the new User or Login ID and password for the financial institution's website and click Continue.
5. Follow the onscreen steps, including any additional security checks your bank might require. It may take a few minutes to connect.
6. Select the bank for the account you want to connect.
7. Hit the Account type drop-down menu to choose either a Bank or Credit Card account.
8. Click Connect

Here's another article for more details about this process: Connect bank and credit card accounts through Banking. 

Second, once your bank account is already refreshed, you can review this article to learn how to categorize and match your bank transactions: Categorize and match online bank transactions in QuickBooks Online.  

Lastly, If you need further assistance while working on your bank account, you can drop a comment here. I'll be sure to get back to you. Stay safe!