I can walk you through changing the vendor's banking info. Fisrt off, we need to update your vendor's bank account info, then toggle the payment method to check to reconnect the correct one.
Then, follow these steps below:
Login to your QuickBooks Online account.
Choose Expenses on the left menu, then select the Pay Bills Online button.
Under the Manage Vendors tab, find the vendor you want to update the bank account for.
Select Set up bank transfers and enter vendor's bank account info.
Click Next., then enter the following required fields and then Save.
For additional reference, you can check these articles:
Yes @pleasegiveusanemail, there is, and I'd be glad to walk you through the process so you can update your vendor's ACH information.
It's essential to keep your vendor information up to date, here's how:
Go to the Expenses tab, then select Vendors.
Click on the vendor's name, then click the Edit button.
The Vendor Information window will pop up.
Scroll down to reach the ACH payments section.
Enter the necessary information you want to update.
Once done, click Save.
Additionally, QuickBooks enables you to monitor and update each vendor's records and transaction status. To learn how to track your vendors' transactions, you might want to read this article: View vendor's transactions.
I'd be happy to assist you anytime if you need further assistance managing your vendors in QuickBooks Online. Please don't hesitate to click the Reply button below.