question about sitemap

You wrote "route" folder, but I assume you meant "root" folder. Right?

You should not expect to be able to see robots.xml with the browser. Actual robots use cURL, file_get_contents() or other means to read the contents of that file.

Try this snippet to read the contents. It assumes that robots.xml is in the same folder with CI's index.php

PHP Code:

$response = file_get_contents('https://yoursite.com/robots.xml');

if (FALSE === $response)
{
    echo "file_get_contents failed";
    return;
}

echo $response;
} 


The display won't be pretty, but you should see the contents.