I can help you with syncing your AMEX transactions in QuickBooks Online (QBO), @Jdean011.

Can you tell me more about the error you're having with AMEX? That'll help us get the best resolution for the error you're having.

For now, you can perform a manual update to get the latest available transactions from your online banking account. 

Here's how: 

1. Go to the Banking menu from the left panel and click the Banking tab. 
2. Select the bank account that you're having trouble with. 
3. Click on the Update button.

This updates your bank and credit card transactions. If you see a message about additional authentication, follow the onscreen instructions. 

After pulling up new transactions you can now categorise and match online bank transactions in QuickBooks Online (QBO) account. 

Here's what you can do if you don’t see your recently downloaded bank transactions in QBO: What to do if you get a bank error or can't download transactions in QuickBooks Online. 

In case, you don't have this option, you can clear your browser's cache or try using other browsers. See this article for detailed guidance: Clear cache and cookies to fix issues when using QuickBooks Online.

I'm always here if you need further guidance in refreshing your bank connections. Let me know in the Reply section below. Have a great rest of the day!