languages switcher is not displayed for users

I added a language switcher to the menu, but only admins can see this properly. When not admin users visit a website, they can see only “Languages” in the main menu, and when they click on it, “/#wpm-languages” adds to the website address. According to the settings, “everyone” should be able to see the languages switcher, but they do not.
I tried to add at the code: ”

<?php
if ( function_exists ( 'wpm_language_switcher' ) ) wpm_language_switcher ();

But it does not help. After adding this code, now visitors on the website can see “Language”(just as before, it does not work, only adds “/#wpm-languages” ) and the main language of the website, which is German. I can not switch the language from German to English as a user, but I can now switch English to German due to this code.
The website was without Elementor Plugin, now it has one, but the problem stays; in this way, it does not impact. Furthermore, I did not mark to show switcher only in one of the languages, so the problem is not there. I tried it on every popular browser and the mobile versions as well; nothing changes.
I would be grateful for your support in solving this non-trivial problem.