Cant get the display manager to load kde

Here is my config file. Please review it and tell me what to do.

# Edit this configuration file to define what should be installed on
# your system.  Help is available in the configuration.nix(5) man page
# and in the NixOS manual (accessible by running ‘nixos-help’).

{ config, pkgs, ... }:

{
  imports =
    [ # Include the results of the hardware scan.
      ./hardware-configuration.nix
    ];

  # Use the systemd-boot EFI boot loader.
  boot.loader.systemd-boot.enable = true;
  boot.loader.efi.canTouchEfiVariables = true;

  # networking.hostName = "nixos"; # Define your hostname.
   networking.wireless.enable = true;   Enables wireless support via wpa_supplicant.

  # The global useDHCP flag is deprecated, therefore explicitly set to false here.
  # Per-interface useDHCP will be mandatory in the future, so this generated config
  # replicates the default behaviour.
  networking.useDHCP = false;
  networking.interfaces.enp2s0f1.useDHCP = true;
  networking.interfaces.wlp3s0.useDHCP = true;

  # Configure network proxy if necessary
  # networking.proxy.default = "http://user:password@proxy:port/";
  # networking.proxy.noProxy = "127.0.0.1,localhost,internal.domain";

  # Select internationalisation properties.
  # i18n = {
  #   consoleFont = "Lat2-Terminus16";
  #   consoleKeyMap = "us";
  #   defaultLocale = "en_US.UTF-8";
  # };

  # Set your time zone.
  # time.timeZone = "Europe/Amsterdam";

  # List packages installed in system profile. To search, run:
  # $ nix search wget
  # environment.systemPackages = with pkgs; [
  #   wget vim
  # ];

  # Some programs need SUID wrappers, can be configured further or are
  # started in user sessions.
  # programs.mtr.enable = true;
  # programs.gnupg.agent = { enable = true; enableSSHSupport = true; };

  # List services that you want to enable:

  # Enable the OpenSSH daemon.
  # services.openssh.enable = true;

  # Open ports in the firewall.
  # networking.firewall.allowedTCPPorts = [ ... ];
  # networking.firewall.allowedUDPPorts = [ ... ];
  # Or disable the firewall altogether.
  # networking.firewall.enable = false;

  # Enable CUPS to print documents.
  # services.printing.enable = true;

  # Enable sound.
sound.enable = true;
hardware.pulseaudio.enable = true;

  # Enable the X11 windowing system.
services.xserver.enable = true;
services.xserver.layout = "us";
services.xserver.xkbOptions = "eurosign:e";
services.xserver.displayManager.sddm.enable = true;
services.xserver.desktopManager.plasma5.enable = true;
hardware.opengl.driSupport32Bit = true;
services.xserver.desktopManager.default = "kde";
services.xserver.displayManager.auto.enable = true;
services.xserver.displayManager.auto.user = "andrew";


  # Enable touchpad support.
  services.xserver.libinput.enable = true;

  # Enable the KDE Desktop Environment.
services.xserver.displayManager.sddm.enable = true;
services.xserver.desktopManager.plasma5.enable = true;

  # Define a user account. Don't forget to set a password with ‘passwd’.
  users.users.andrew = {
     isNormalUser = true;
     extraGroups = [ "wheel" ]; # Enable ‘sudo’ for the user.
   };

  # This value determines the NixOS release with which your system is to be
  # compatible, in order to avoid breaking some software such as database
  # servers. You should change this only after NixOS release notes say you
  # should.
  system.stateVersion = "19.09"; # Did you read the comment?

}

I see you in my inbox, did you replie or make a change?

I don’t think the session is called kde.
So your config should be

services.xserver.desktopManager.default = "plasma5";

and autologin should be fine.

(note these could be changing in the next release)