Issues configuring msmtp using the home-manager module.

[AZMCode]

Currently my accounts and msmtp configuration looks like this:

  programs.msmtp = {
    enable = true;
  };
  accounts.email.accounts.default = {
    primary = true;
    msmtp = {
      enable = true;
      extraConfig = {
        host = "<redacted>";
        from = "<redacted>";
        port = 1134;
        auth = "on";
      };
    };
  };

And when during evaluation I get the following error log:

building the system configuration...
warning: Git tree '/home/adriano/Documents/Personal/nixos-config' is dirty
error:
       … while calling the 'head' builtin
         at «github:nixos/nixpkgs/d233902339c02a9c334e7e593de68855ad26c4cb?narHash=sha256-30s
ZNZoA1cqF5JNO9fVX%2BwgiQYjB7HJqqJ4ztCDeBZE%3D»/lib/attrsets.nix:1712:13:
         1711|           if length values == 1 || pred here (elemAt values 1) (head values) t
hen
         1712|             head values
             |             ^
         1713|           else

       … while evaluating the attribute 'value'
         at «github:nixos/nixpkgs/d233902339c02a9c334e7e593de68855ad26c4cb?narHash=sha256-30s
ZNZoA1cqF5JNO9fVX%2BwgiQYjB7HJqqJ4ztCDeBZE%3D»/lib/modules.nix:1167:7:
         1166|     // {
         1167|       value = addErrorContext "while evaluating the option `${showOption loc}'
:" value;
             |       ^
         1168|       inherit (res.defsFinal') highestPrio;

       … while evaluating the option `system.build.toplevel':

       … while evaluating definitions from `/nix/store/77dbgds155bbz3vd3qywq1sii07i5ljs-sourc
e/nixos/modules/system/activation/top-level.nix':

       … while evaluating the option `warnings':

       … while evaluating definitions from `/nix/store/77dbgds155bbz3vd3qywq1sii07i5ljs-sourc
e/nixos/modules/system/boot/systemd.nix':

       … while evaluating the option `systemd.services.home-manager-adriano.serviceConfig':

       … while evaluating definitions from `/nix/store/fn117mi04ccnvvj6vxn34pdj33prmr7i-sourc
e/nixos':

       … while evaluating the option `home-manager.users.adriano.home.file."/home/adriano/.co
nfig/msmtp/config".source':

       … while evaluating definitions from `/nix/store/fn117mi04ccnvvj6vxn34pdj33prmr7i-sourc
e/modules/files.nix':

       … while evaluating the option `home-manager.users.adriano.home.file."/home/adriano/.co
nfig/msmtp/config".text':

       … while evaluating definitions from `/nix/store/fn117mi04ccnvvj6vxn34pdj33prmr7i-sourc
e/modules/misc/xdg.nix':

       … while evaluating the option `home-manager.users.adriano.xdg.configFile."msmtp/config
".text':

       … while evaluating definitions from `/nix/store/fn117mi04ccnvvj6vxn34pdj33prmr7i-sourc
e/modules/programs/msmtp':

       … while evaluating the option `home-manager.users.adriano.programs.msmtp.configContent
':

       … while evaluating definitions from `/nix/store/fn117mi04ccnvvj6vxn34pdj33prmr7i-sourc
e/modules/programs/msmtp':

       (stack trace truncated; use '--show-trace' to show the full, detailed trace)

       error: expected a set but found null: null
Command 'nix --extra-experimental-features 'nix-command flakes' build --print-out-paths '.#ni
xosConfigurations."workstop".config.system.build.toplevel'' returned non-zero exit status 1.

nix-info output:

 - system: `"x86_64-linux"`                                                                  
 - host os: `Linux 6.18.31, NixOS, 26.05 (Yarara), 26.05.20260515.d233902`                   
 - multi-user?: `yes`                                                                        
 - sandbox: `yes`                                                                            
 - version: `nix-env (Nix) 2.34.7`                                                           
 - channels(root): `"nixos, nixpkgs"`                                                        
 - nixpkgs: `/nix/store/77dbgds155bbz3vd3qywq1sii07i5ljs-source`

What am I doing wrong here?