Even if you start theia with GCP serverless, you can't access it.

[secmin]

nodejs: v12.18.3
debian: 9.13
browser: chrome

What I've tried.
I switched ports a couple of times to access it.
I checked my browser and GCP firewall settings.
I checked my PC's proxy settings.

I tried to access it a few times, but I can't access it and it times out.
Is there anything else I can try?