Vpn подключение между iOS NEVPNManager и StrongSwan на Ubuntu 16.04

Я пробую сделать подключение между в своем приложении. На сервере используются StrongSwan и Ubuntu 16.04. Сделано по этому гайду. При попытки подключится к серверу он выдает эти логи:

 - May  5 08:58:21 ip-2 charon: 05[NET] received packet: from 3[500] to 2[500] (432 bytes)
 - May  5 08:58:21 ip-2 charon: 05[ENC] parsed IKE_SA_INIT request 0 [ SA KE No N(REDIR_SUP) N(NATD_S_IP) N(NATD_D_IP) N(FRAG_SUP) ]
 - May  5 08:58:21 ip-2 charon: 05[IKE] 3 is initiating an IKE_SA
 - May  5 08:58:21 ip-2 charon: 05[IKE] local host is behind NAT, sending keep alives
 - May  5 08:58:21 ip-2 charon: 05[IKE] remote host is behind NAT
 - May  5 08:58:21 ip-2 charon: 05[IKE] received proposals inacceptable
 - May  5 08:58:21 ip-2 charon: 05[ENC] generating IKE_SA_INIT response 0 [ N(NO_PROP) ]
 - May  5 08:58:21 ip-2 charon: 05[NET] sending packet: from 2[500] to 3[500] (36 bytes)
 - May  5 08:58:22 ip-2 charon: 16[NET] received packet: from 3[500] to 2[500] (432 bytes)
 - May  5 08:58:22 ip-2 charon: 16[ENC] parsed IKE_SA_INIT request 0 [ SA KE No N(REDIR_SUP) N(NATD_S_IP) N(NATD_D_IP) N(FRAG_SUP) ]
 - May  5 08:58:22 ip-2 charon: 16[IKE] 109.202.21.168 is initiating an IKE_SA
 - May  5 08:58:22 ip-2 charon: 16[IKE] local host is behind NAT, sending keep alives
 - May  5 08:58:22 ip-2 charon: 16[IKE] remote host is behind NAT
 - May  5 08:58:22 ip-2 charon: 16[IKE] received proposals inacceptable
 - May  5 08:58:22 ip-2 charon: 16[ENC] generating IKE_SA_INIT response 0 [ N(NO_PROP) ]
 - May  5 08:58:22 ip-2 charon: 16[NET] sending packet: from 2[500] to 3[500] (36 bytes)

Так же вот код на который используется для подключения.

class VpnManager {
    
    let vpnManager = NEVPNManager.shared()
    let info = VPNINFO()
    
    func connectToVPN() {
        vpnManager.loadFromPreferences { error in
            guard error == nil else {
                print(error)
                return
            }

            let IKEv2Protocol = NEVPNProtocolIKEv2()
            IKEv2Protocol.serverAddress = self.info.serverAddress
            IKEv2Protocol.authenticationMethod = .certificate
            
            let certificate = SecCertificateCreateWithData(nil, Data(base64Encoded: self.info.cert)! as CFData)!
            let certificateData = SecCertificateCopyData(certificate) as Data
            IKEv2Protocol.identityData = certificateData
            
            self.vpnManager.protocolConfiguration = IKEv2Protocol
            self.vpnManager.isEnabled = true
            
            self.vpnManager.saveToPreferences { error in
                guard error == nil else {
                    print(error)
                    return
                }
                do {
                    try self.vpnManager.connection.startVPNTunnel(
                        options: ([
                            NEVPNConnectionStartOptionUsername: "username",
                            NEVPNConnectionStartOptionPassword: KeychainWrapper.passwordRefForVPNID("MY_PASSWORD")
                        ] as! [String: NSObject]))
                } catch let error {
                    print(error)
                }
            }
        }
    }
    
    
}

Ожидаемый результат: Соединение установлено.

Текущий результат: Подключился -> Отключился