I had the same problem. The server that I am running off is behind a router, and when trying to log-in as admin for the first time, it would keep going back to the same page. Because the server itself has a local IP address, the default options aren’t going to work. Adding these lines to my wp-config.php fixed this, of course substitutiing the actual URL for your blog:
define('WP_SITEURL', 'https://www.sample.com/wordpress');
define('WP_HOME', 'https://www.sample.com/wordpress');
More can be found here.
Hope this helps.
