public function store(CreateUserRequest $request)
{
    $user=new User;
    $user->first_name=$request->first_name;
    $user->last_name=$request->last_name;
    $user->email=$request->email;
    $user->password=$request->password;
    $user->save();

    return redirect("panel/user");
}

<?php

protected $fillable = [
    'first_name', 'last_name', 'email', 'profile_id', 'status_type_id', 'udn_id', 'user_type_id'
];

protected $hidden = [
    'password', 'remember_token'
];

protected $dates =["deleted_at"];

public function Udn(){
    return $this->belongsTo('AppUdn', 'udn_id');
}

<?php

protected $fillable = [
    'name', 'slug', 'status_type_id'
];

protected $dates =["deleted_at"];

    protected function User(){
    return $this->hasMany('AppUser');
}