It's my top priority that you can get in touch with the Phone or Chat Support Teams and get this billing matter straightened out. To clarify, what is the error message you're receiving when trying to access the in-product help menu? I'd recommend clearing your browser's temporary cache files and trying to access again.
Web-based platforms such as QBO collect cache files (cookies) to save you time when loading repetitive data and images. These files can often become outdated or corrupted, causing issues like the one with your in-product Help menu. You can clear those files using the instructions below:
Doing this will force QBO to load a fresh copy of everything on the screen, allowing you to properly get in touch with the Phone or Chat Support Teams. Please let me know if there's anything else I can do to help you out, I'm here to ensure your success. Thanks for dropping in and take care.