We have an ongoing investigation on connecting with the First National Bank of PA. This has been raised to the banking engineers to fix this unexpected behavior. I recommend getting in touch with our QuickBooks Online Support. They have the tools to add you to the list of affected users, so you'll receive an email notification once the issue got fixed.
Support hours are from Monday to Friday 6 AM to 6 PM and Saturday 6 AM to 3 PM PT.
In addition, I've also included this article to learn how you can manually upload bank transactions into QuickBooks Online: Manually upload transactions into QuickBooks Online.
Let me know if you have further questions or concerns about banking. I'll be here to help you out.