Having issues with connecting Amex Business Card Error 357

Let's discuss the error and resolve it to connect the bank successfully, chestateellc.

You'll encounter this error when secondary users attempt to connect the bank to QuickBooks Online (QBO) using their credentials. To resolve this, use the primary user's credentials to link the American Express account.

In the meantime, you can add those missing transactions through the WebConnect process. You’ll have to manually download the transactions from the bank. Then, upload the file to your account. Here's how:

1. Go to your online banking account to get your file.
2. Check or follow your bank’s instructions to get a copy of the data and then save it on your computer.
3. Ensure that the data range is at least one day before your oldest transaction to avoid duplicates.
4. Please take note of the supported file format and size. It should be either a Comma-Separated Values (CSV) or a QuickBooks Online (QBO) file. 
5. Download your transactions and save the file to your desktop. 

To upload the file to your QuickBooks account: 

1. Go to the Banking menu and select the bank where you’re uploading the transactions from the Banking tab.
2. Click the Lin account drop-down and select Upload from file.
3. On the window that appears, click the Browse button and choose the file that you’ll be downloading. 
4. Click on Open, then Next.
5. Follow the onscreen instructions. Match the columns on the file with the banking fields in QuickBooks, then select Next.
6. Click on Let's go. 

Check this article for more information: Manually upload transactions into QuickBooks Online. From here, you can now categorize and then reconcile the transactions.

Let me know if there’s anything else that I can assist with about your bank account by leaving a comment below. I’m always here to assist.