Website down in specific regions

Our application loads in some regions (Seattle) but not in others (San Francicso). In San Francisco, it loads a black screen. I suspect Cloudflare may be running into issues in this region. If I VPN to US central or Europe, the application works. Any idea how we can debug this?

Our tech stack is a react app on google k8s. Surprisingly, the django backend (admin frontend UI) is still deployed and operational in San Francisco.

I just purged the Cloudflare cache and it fixed the issue. Any insight on this?