.htaccess rewrite problem

Question

Having a weird problem.

I have two sites, first is www.example.com/folder/site1/, second is www.example.com/folder/site2/.

The problem I have is that my .htaccess code is only working on site1, why?

My .htaccess code looks like this:

RewriteEngine On
RewriteBase /folder/site1/

# Do not enable rewriting for files or directories that exist
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.?)\/$ index.php?page=$1 [NC,QSA]

This works fine for site1, but if I use the same (except changing the Base) it doesn't work. The file is located in /folder/site#/.htaccess