Post values from POSTMAN is returning empty array

I want to get values from postman, all I am getting is empty response. I want to save values in database by getting all the values from postman. Postman settings are okay. There is problem with my code because I am not getting the values. Following is the code I am using in controller:-

public function save_user_details(Request $request){

    $data = $request->all();

    //return $response = array('status'=>'true');

    if(!isset($data['full_name']) && empty('full_name')){
        $result['status']   =  false;
        $result['message']  =  "Full name is required";
    }else if(!isset($data['mob_num']) && empty($data['mob_num'])){
        $result['status']   =  false;
        $result['message']  =  "Mobile Number is required";
    }else if(!isset($data['password']) && empty($data['password'])){
        $result['status']   =  false;
        $result['message']  =  "total_cost is required";
    }else if(!isset($data['age']) && empty($data['age'])){
        $result['status']   =  false;
        $result['message']  =  "age is required";
    }else if(!isset($data['city_id']) && empty($data['city_id'])){
        $result['status']   =  false;
        $result['message']  =  "City is required";
    }else{

        $full_name      = $data['full_name'];
        $mobile_number  = $data['mob_num'];
        $password       = $data['password'];
        $age            = $data['age'];
        $state          = $data['state'];
        $city           = $data['city'];
        $post           = $data['post'];
        $created_at     = date("Y-m-d H:i:s");

        $country_code   = '91';

    if($full_name != '' && $mobile_number != '' && $password != ''
        && $age != '' && $city != ''){

        DB::table('pmjkyppa_users')->insert([
            ['full_name' => $full_name, 'mob_num' => $country_code.$mobile_number, 
            'password' => md5($data['password']), 'age' => $age, 'state' => $state, 'city' => $city, 
            'post' => $post, 'created_at' => $created_at, 'updated_at' => '']
        ]);
            $result['status']   =  true;
            $result['message']  =  "Saved!";

    }else{
            $result['status']   =  false;
            $result['message']  =  "Plese Fill in your details!";

    }
    }
    echo  json_encode($result);

}

And following is the route:-

Route::match(['get','post'],'/pmjkyppa_register','pmjkyppa\HomeController@save_user_details'