NEVPNProtocolIPSec unavailable on Apple TV?

Question

I'm porting my VPN app to tvOS 17. In iOS the VPN connects successfully, however in tvOS saveToPreferences returns error Code 1: Could not save VPN Configurations: Missing protocol or protocol has invalid type

Could you advise what's the problem with my code?

 func toggleVPN() {
    let vpnManager = NEVPNManager.shared()

    vpnManager.loadFromPreferences { (error) in
      if let error = error {
        print("Could not load VPN Configurations: \(error.localizedDescription)")
        return
      }

      if vpnManager.connection.status == .connected || vpnManager.connection.status == .connecting {
        vpnManager.connection.stopVPNTunnel()
      } else {
        vpnManager.isEnabled = true
        vpnManager.isOnDemandEnabled = true
        vpnManager.localizedDescription = "tvpn"
        let p = NEVPNProtocolIPSec()
        p.authenticationMethod = .sharedSecret // or .certificate
        p.serverAddress = <REDACTED>
        p.username = "client"
        p.useExtendedAuthentication = true
        // Retrieve password and shared secret references from the keychain

        let secretData = <REDACTED>.data(using: .utf8)!
        let passData = <REDACTED>.data(using: .utf8)!
        p.sharedSecretReference = try! VPNKeychain.persistentReferenceFor(service: "vpn", account: "SharedSecret", password: secretData) // I took this part from Apple dev forums, it's tested in iOS
        p.passwordReference = try! VPNKeychain.persistentReferenceFor(service: "vpn", account: "Password", password: passData)

        vpnManager.protocolConfiguration = p
        vpnManager.saveToPreferences { (error) in
          if let error = error {
            print("Could not save VPN Configurations: \(error.localizedDescription)")
            return
          }

          do {
            try vpnManager.connection.startVPNTunnel()
          } catch {
            print("Could not start VPN Connection: \(error.localizedDescription)")
          }
        }
      }
    }
  }

persistentReferenceFor implementation can be found here: https://developer.apple.com/forums/thread/84194?answerId=252309022#252309022

This code without any changes works on iOS

Another thing I noticed, is that there's no com.apple.developer.networking.vpn.api entitlement for tvOS 17, but NEVPNManager is available there according to documentation.