Implement NextDNS and Wireguard in swift

I have configured NextDNS in my code using the following DNS servers:
45.90.28.79, 45.90.30.79

I am using WireGuard with different VPN servers (e.g., Ohio, Japan, South Korea). Each server has a unique public IP.

When I connect to a specific VPN server and test with https://test.nextdns.io, I get the following response:
{
  "status": "ok",
  "protocol": "UDP",
  "profile": "fp0ecef16aa6f05ef6",
  "client": "54.219.109.29",
  "srcIP": "54.219.109.29",
  "destIP": "45.90.28.79",
  "anycast": true,
  "server": "vultr-sjc-1",
  "clientName": "unknown"
}

As you can see, the clientName is "unknown". I would like to resolve this issue so that the correct client name is displayed. Could you please guide me on how to fix this?

Thanks,