Use reverse proxy in front of blynk local server

Blynk Servers Local Blynk Server
1

Hello,

I start a docker with blynk server on it, to acces to the admin i create a reverse proxy (Caddy) who generate ssl certificate automatically.

https://blynk.mydns.org {
  proxy / https://blynk-docker:9443 {
    websocket
    insecure_skip_verify
    transparent
  }
  gzip
  timeouts 300s
  proxyprotocol 0.0.0.0/0
  log / stdout "{hostonly} - {combined}"
}

I have access to the admin interface, but for some strange reason the app wont connect to my server and tell me:

Something went wrong when connecting to the server. Please check port 443 port is open in your network.

when i go without the proxy it work, I also try to use the port 9443 but still not working.

I understand the problem is from the proxy but i can manage where because i have access to the admin console

Can you help me ?

Thanks