Blank Login pages (mac and pc) after changing site/wp address in settings

Hi there, I am working on a client’s site and currently neither her nor I can get in the backend of the site’s admin panel. There is currently only a blank page. this happened after I adjusted the settings (Settings>General) for the site url and the blog url and made them different https://www.siteurl.com vs https://siteurl.com. I’ve tried to adjust it in the wp-config file with these commands:
define(‘WP_SITEURL’, ‘https://shoplocalsd.com’);

define(‘WP_HOME’, ‘https://shoplocalsd.com’);

but to no avail. now the site doesn’t render if you type in the url WITH the WWW.

The original general settings were both set to the url WITHOUT the www.

Please help ??