Because of an issue of fraudulent activity on my account all balances and information were transferred to a new account. How can I update and connect my new account?

Welcome to the Community, @theronnjensen. I'm delighted to guide you in connecting the new account in QuickBooks Online.

Ideally, we'll have to first review all transactions that are in the For Review as it will be deleted once we disconnect the old account.

In your case where all balances and information from the old account were transferred to the new one, we can disconnect it right away. Here's how:

1. Go to the Banking menu.
2. Click the bank that you'll need to disconnect.
3. At the upper-right of the bank tile, click the pencil icon.
4. Check the Disconnect this account on save box.
5. Hit Save and Close.

Then, follow the steps to connect the new account for online banking. Should you want to use the same register, make sure that you pick the correct account in the Which accounts do you want to connect? section during the connection process. 

For future reference, read through this article: Categorize and match downloaded transactions in QuickBooks Online. It also includes steps to exclude duplicates in case you have one. 

Feel free to message again if you have additional questions. We're always delighted to assist.