[Risolto] href lang x-default

Background of the issue:
We have noticed that our posts have the exact same "href lang x-default" value no matter their language. For instance, this Spanish post (Spanish is the default language), link nascosto and the English translation, link nascosto share these same values:

There is absolutely no difference, the code and the order is identical. Semrush and GSC are indicating multiple href lang errors on our site raypa.com, but then when I examine each page, the href code looks fine to me. I am following the documentation at https://wpml.org/documentation/support/adding-hreflang-wordpress/

Symptoms:
Semrush and GSC are indicating multiple href lang errors on our site raypa.com.

Questions:
Is it correct that our posts have the exact same "href lang x-default" value no matter their language?
Should the href lang values be different to indicate the language of the post?
Is everything fine with our current href lang setup?