`
define( ‘WP_HOME’, ‘https://yourdomain.com’ );
define( ‘WP_SITEURL’, ‘https://yourdomain.com’ );
`

However, it is best to contact your hosting provider and try to find the cause for the redirect loop error.

Also,
Go to your site backend (if you can access)

Settings > General >
Change the site URL

WordPress Address (URL)
https://www.alphabetpublishingbooks.com/

and,

Site Address (URL)
https://www.alphabetpublishingbooks.com/

Check this screenshot: https://i.imgur.com/aHwyJCj.png

If you can’t access your site backend, you can do that by phpMyAdmin.

Hope it helps you.