I'll make sure that you'll be able to connect your First National Bank(FNB) account to QuickBooks Online(QBO).
Before I provide you any information, I'd like to know if you're getting any error messages when connecting your bank account. This way, we'll be able to determine the reason behind it and offer you the best resolution.
For now, you can log in to your website and check if there's an ongoing issue on their end.
Here's how:
Use the URL QuickBooks uses to connect by going to Banking menu, then select Link account.
Locate your bank, then copy the URL listed for your bank.
Use the URL to sign in to your bank's website.
Check for messages, notifications, or alerts in your account.
While navigating the website, check for any display issues. These can enable QuickBooks to download new transactions.
Check for any alerts about new security requirements in your bank’s website.
If everything's okay, go to the Banking menu, then Banking tab.