Caching Affecting Sub-domains

I noticed a weird behavior for my systems running on sub-domains of the main wordpress domain. and this only happened after upgrading the WP Fastest Cache Plugin from version 0.8.6.3 to 0.8.6.8

now my systems is caching pages from one signed-in user and view it to all users trying to access this system with the name of the first user.

I don’t know how but I don’t have any settings in subdomain .htaccess file, So WP Fastest Cache is affecting sub-domains with sub-directories in my main wordpress location.

Please help me fix this or send me old version to rollback to it.

P.S. I have tried to disable caching on my sub-domains by putting this to it’s .htaccess files but there is nothing changed:

RewriteEngine On
RewriteRule ^(.*)$ $1 [NS,E=no-gzip:1,E=dont-vary:1]

SetEnv no-gzip 1

# DISABLE CACHING
<IfModule mod_headers.c>
#	Header set Cache-Control "max-age=0, private, no-cache, no-store, must-revalidate
	Header set Cache-Control "no-cache, no-store, must-revalidate
	Header set Pragma "no-cache"
	Header set Expires 0
</IfModule>