Error on switching the language

Hello,
i have a problem with this wonderful plugin.

If you go to my web site https://www.giast.com/photography/blog/ and then try to go to my multilanguage sections like german or english, you will be redirect to a specific blog post and not, as expected, to the root (like https://www.giast.com/photography/blog/de or https://www.giast.com/photography/blog/en) where you can found all the blog posts in a list.

After many tries, i cant be able to understand why this happen. Anyone can help me?

Thank you in advance.