@maya-ekron Hi again! Thanks for your help, it works 
But I got the problem.
I changed the post page. I use the page title that I get using getPost. I also added post navigation. When I open a post for the first time - OK, the title gets the value. But if I use navigation inside the post, the title does not update its value. The post page does not reload?
My site and post
(only for desktop)