[تم الحل] I need help with WPML redirections

Background of the issue:
I am trying to load my site on the default /es URL, but it is showing a 500 error. The issue can be seen at الرابط المخفي.

Symptoms:
I expected to see the site's homepage, but instead, I got a 500 error.

Questions:
Why is my site showing a 500 error when trying to load the default /es URL?
How can I resolve the 500 error to display the site's homepage?