Web App Access Issue on Home Network

I'm facing an issue with a web application that I can access outside of my home network, but not while I'm connected to my home internet. The application doesn't load or respond at all. I've already tried multiple browsers and the issue persists across all of them.

I need a professional to:
- Diagnose the issue with my home network
- Determine if it's a network-wide issue or specific to my PC
- Suggest possible solutions or fixes

Ideal skills for this project include:
- Network troubleshooting
- Experience with diagnosing web application issues
- Ability to provide clear, understandable explanations and solutions