Have your full .htaccess like this:
RewriteEngine On
## add www and turn on https in same rule - main domain
RewriteCond %{HTTP_HOST} !^www\. [NC,OR]
RewriteCond %{HTTPS} !on
RewriteCond %{HTTP_HOST} ^(?:www\.)?(example\.com)$ [NC]
RewriteRule ^ https://www.%1%{REQUEST_URI} [R=301,L,NE]
## turn on https in same rule - sub domain
RewriteCond %{HTTPS} !on
RewriteRule ^ https://%{HTTP_HOST}%{REQUEST_URI} [R=301,L,NE]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^ index.php [L]
Make sure to use a new browser to test your changes to avoid old browser cache.
4
solved Move to https://www, when it is www or http:// or without www and http://?