Bug languages switch

Good Day!

First of all, I would like to thank you for your stunning plugin. It is very useful and easy . Good Job 😉

However, I just have a small problem. When I want to switch from a language to another one, it works perfectly with the pages and categories I created by myself on my theme (Neighborhood). But when I wanna switch languages with the native pages or options from the theme, it comes back to the main language.
Ex: The default language is English – The second language is French. On the homepage, if you switch to French and then if you click on “sign up” or “login” for example, the next page switches back to the default language.

It can be annoying if my customers have to switch to another language each time a new page appears. Could you please help me to fix it?

My website is http://www.paperandcrafts.com if you wanna have a look.

Thanks again !

https://ww.wp.xz.cn/plugins/ceceppa-multilingua/