WP Admin gives me 404 error

I’m facing the problem since version 4.8
till now, after manually updating to 4.8.2
wp-admin gives me 404 error on some pages, and I have to refresh the page many times to load fine!
case:
page https://www.domain.com/wp-admin/update-core.php
gives me 404 error, and after some page refresh, it loads fine, but after choosing plugins to update, and press update plugins, I got 404 error page again.