Wrong redirect for website in subfolder

Hello,

I have a main site in my root and a subsite in a separate folder.

When I choose this subfolder (mysite.com/subsite – without https//) in my browser, only the root folder opens. This will show https:// in front of it

When I type in the full path, https://mysite.com/subsite it works immediately

This is my .htaccess file

# BEGIN rlrssslReallySimpleSSL rsssl_version[4.0.13]
<IfModule mod_rewrite.c>
RewriteEngine on
RewriteCond %{HTTPS} !=on [NC]
RewriteRule ^(.*)$ https://%{HTTP_HOST}/$1 [R=301,L]
</IfModule>
# END rlrssslReallySimpleSSL
# BEGIN WordPress
# De richtlijnen (regels) tussen "BEGIN WordPress" en "END WordPress" worden
# dynamisch gegenereerd en zouden alleen aangepast mogen worden via WordPress filters.
# Alle wijzigingen aan de richtlijnen tussen deze markeringen worden overschreven.
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
RewriteBase /subsite/
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /subsite/index.php [L]
</IfModule>

# END WordPress

When I delete the following data it works correctly.

# BEGIN rlrssslReallySimpleSSL rsssl_version[4.0.13]
<IfModule mod_rewrite.c>
RewriteEngine on
RewriteCond %{HTTPS} !=on [NC]
RewriteRule ^(.*)$ https://%{HTTP_HOST}/$1 [R=301,L]
</IfModule>
# END rlrssslReallySimpleSSL

Any idea?
Thanks