Polylang language switcher links to wrong url

I am working on my bilingual website with wordpress and the polylang plugin! The problem is that when I click on the language switcher to change from deutsch to english language the page cannot be found because it points to the wrong url (www.florian-drums.com/en instead of https://www.florian-drums.com/en/drumlessons). Is there a way to edit the url link from the language switcher?

The problem only occurs when I first click on the language switcher. After I click on the switcher, there is this error page, but the menu changes to english and from there I can reach all english pages perfectly

Here is the website: https://www.florian-drums.com

Please help!

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