Hi there, aceadiahuang.
We'll help you resolve this issue and set up your bank account in QuickBooks Online (QBO).
Error 169 typically occurs when you add the same account to your profile more than once. When two accounts have the exact same details, the system gets confused and doesn’t know which one to update. As a result, the account ends up in an error status.
To fix this problem, you should contact your bank and ask them to rename or change the account numbers for your accounts so they can be uniquely identified. This will help you connect the accounts properly in QuickBooks Online (QBO).
If you have added a duplicate bank account, you can disconnect the account. You can read this article to help you delete a bank account connected to QBO. Disconnect accounts connected to QuickBooks Online.
If you have additional questions, feel free to reply in this thread.