Subject: Custom domain resets connections from Russian mobile networks while Railway domain works

Hello.

My Railway-generated domain works from Russia:

https://smartroute.up.railway.app/

My custom domain is verified and routed through Cloudflare:

https://smartroute.press/

From a Windows network in Russia, this command works:

curl.exe -4 -v https://smartroute.press/

It returns:

HTTP/1.1 200 OK

Content-Type: text/html; charset=utf-8

x-railway-request-id: Gt12Rm7hT5a3B-yQCYBc-A

x-railway-edge: cdg1

However, Chrome on Android/iOS mobile networks without VPN returns:

ERR_CONNECTION_RESET.

Cloudflare trace from the same mobile device:

fl=1041f35

h=smartroute.press

loc=RU

colo=FRA

http=http/2

tls=TLSv1.3

sni=plaintext

warp=off

DNS:

smartroute.press CNAME an3dje18.up.railway.app

www.smartroute.press CNAME d0ybk1nd.up.railway.app

Both custom domains are proxied by Cloudflare.

SSL mode: Full.

Please check:

1. Custom-domain TLS certificate provisioning.
2. Railway edge routing for smartroute.press and www.smartroute.press.
3. Whether the certificate is deployed on all Railway edge locations.
4. Whether the custom-domain hostnames are routed differently from the generated Railway domain.

Please refresh/redeploy the custom-domain certificate and edge routing if necessary.