Allow me to help and isolate the error you received on your end.
Recently, we updated our bank feed connections to open banking to give our user a better experience. Thus, the reason you received the error means the bank you’re trying to connect to QuickBooks Online (QBO) is not yet supported for open banking.
Rest assured our product team is working with other financial institutions to provide Open Banking connections. In the meantime, let’s manually import your bank transactions to your account. Let me show you how:
Sign in to your Amazon Business account and follow the instruction on how to download the transactions.
Review the file format (.QBO or .CSV file) and size (maximum file size is 350 KB).
Then from your QBO account, go to the Banking menu or Transactions menu.
Select Upload transactions.
Click Browse and then select the file you downloaded from your bank. Then select Next.
In the QuickBooks account drop-down, select the account you want to upload the transactions into. Then click Next.
Follow the onscreen steps to match the columns on the file with the correct fields in QuickBooks. Then select Next.