getClientIp() gives server IP or Random IP rather than visitor IP

[a21ns1g4ts]

Symfony version(s) affected: 5.0

Description
I'm trying to track IP addresses of visitors. When using getClientIp(), I get the server's IP address rather than the visitor's. I tried this on multiple machines at multiple locations and they all resulted in the exact same IP.
I have look at the follow line:
https://github.com/symfony/http-foundation/blob/0553e8b8cb3a48d6b84a91968871e6e14d5602a4/Request.php#L798

public function getClientIps()
{
   $ip = $this->server->get('REMOTE_ADDR');

   if (!$this->isFromTrustedProxy()) {
       return [$ip];
  }

  return $this->getTrustedValues(self::HEADER_X_FORWARDED_FOR, $ip) ?: [$ip];
}

How to reproduce
I have noted this behavior in my network. But i have the problems with this method in heroku. The results ip's are random in some cases. I have used https://ngrok.com/ for local tests. I have a visitor tracker made with on rails and it works for all network and all cases.
I have tested in my heroku server and i have catch the results:
Different ips for same client.

In my ruby application running in heroku always it works:

Possible Solution

👀
Additional context
Test locally with ngrock

public function getClientIps()
{
  $ip = $this->server->get('REMOTE_ADDR');

   // if (!$this->isFromTrustedProxy()) {
   //   return [$ip];
   // }
      var_dump($this->getTrustedValues(self::HEADER_X_FORWARDED_FOR, $ip))
      return $this->getTrustedValues(self::HEADER_X_FORWARDED_FOR, $ip) ?: [$ip];
}

Output

^ array:2 [▼
  0 => "127.0.0.1"
  1 => "177.66.107.164"
]

[xabbuh]

Well, if your web server is behind a proxy server, you will indeed have to configure the trusted proxies to retrieve the real client IP address.

[xabbuh]

see https://symfony.com/doc/current/deployment/proxies.html

[a21ns1g4ts]

yep, but a lot of symphony dependents don't know this behavior. I have used several http kernels and only symphony has this behavior.