However, if the issue persists with the other troubleshooting steps, I'd recommend contacting our Customer Support Team. They have the tools to pull up your account in a secure environment and create a report about this behavior.
Stay in touch with us if you have other questions. I'm always here to lend you a helping hand. Take care!
I appreciate the things you've done to fix this issue. Since you're still not able to connect to your bank after following the steps shared by my colleague, I'd recommend contacting our Customer Care Team. They have the tools to perform screen-share and check further what has caused this issue to get to the bottom of this.
Here's how to contact them:
Go to the Help menu and select QuickBooks Desktop Help.
Select Contact us.
Enter your concern and choose Messaging.
Enter your details and wait for the available agent to assist you.
You may also check our support hours before contacting our support team to know the best time to call at your convenience.