Welcome to the Community. I'd be glad to assist with the Pay Bills Online option loading a white screen.
Generally, when a user encounters unexpected behavior in QuickBooks, it's recommended to try browser troubleshooting. If you haven't done so, I suggest clearing the cache of your browser. Cache is stored in order to speed up loading times, but this can impact processes and cause them to not work. For additional information on this and steps for supported browsers, please visit the following link: How Do I Clear My Browser Cache And Temporary Internet files?.
Lastly, you may wish to consider contacting the Phone Support Team. This team can pull up your account in a secure environment and has specialized tools to assist with connectivity. Here's how you can reach them: