When you mentioned bank account, there are different areas we can review. It could be the bank account:
If you're referring to the actual bank account connected to the Banking page, you can review the sign-in info. Here's how:
If the details you're looking is the QuickBooks bank account connected to the real one, you can select the Edit account info button. It'll open the account information of the QuickBooks bank account.
If you're referring to the Chart of Accounts page, you'll need to enable the account numbers to see and add them to the accounts. Here's how:
When you go back to the Chart of Accounts page, you can see the NUMBER column. With that, you can enter account numbers in bulk.
After that, you can sort the list by clicking the column headers.
For transactions, you might want to open them manually to see the affected accounts.
There are many ways to go around in QuickBooks Online. Additional details of what you're looking for would be great so we can pinpoint and provide the steps. Have a great day!
You will need the bank website login Credentials, from there you can review the details of the real bank account (sort code and account Number). If unsure about these you will need to speak to the Client.