detect browser language redirect to wrong page

Hello,

we have the following problem: we have one homepage in English and another one in German. We would like to set it so that the language is set according to “detect browser language”. However, when we enable this, all visitors (no matter what language) are redirected to a fixed German URL, which is even not the German homepage, but another page on our website. When we deactivate “detect browser language” everything is normal and the correct website is displayed.

How can we change this? And where can we change the settings of the redirection to the corresponding page?

Many thanks in advance.