Why redirect only the main page?

Question

Apache HTTP Server

ftl.by/uslugi/avia-perevozki
The following is written in htacess

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
RewriteCond %{SERVER_PORT} !^443$

RewriteRule .* https://%{SERVER_NAME}%{REQUEST_URI} [R=301,L]
</IfModule>
# END WordPress

In wp-config, this is it
$_SERVER['HTTPS'] = 'on';
Please tell me what's wrong?