Flask sub.domain.com overrides session on domain.com - session

Question

I have two seperate server one for domain.com and another for sub.domain.com, and I store sessions using flask-session and following configuration:
SERVER_NAME = 'domain.com'
SESSION_COOKIE_DOMAIN = ".domain.com"
# Flask-Session
SESSION_TYPE = 'redis'
SESSION_REDIS = Redis(host='192.168.10.10', port=6379, db=0)
further more I am using reverse proxy using nginx and:
proxy_set_header Host $host;
When I login on domain.com everything is ok but when I refresh sub.domain.com, user logs out on domain.com(sub.domain.com creates another session and overrides the one which is created by domain.com). Authentication is done by flask-login and it's on domain.com (sub.domain.com only should get them).
I don't know what's going wrong and I appreciate any help.
Update:
I tried to run flask without uwsgi and it works as it should, but when I uwsgi and nginx the problem persists. I think something is wrong with my uwsgi or nginx config.
# uwsgi.ini
[uwsgi]
master = true
enable-threads = true
process = 3
plugin = python
socket = /tmp/name.sock
base = /var/www/app
chdir = %(base)
wsgi-file = %(base)/manage.py
callable = app
# nginx.conf
server {
listen 8001;
location / {
include uwsgi_params;
uwsgi_pass unix:///tmp/name.sock;
}
}

Answer 1

By mistake I thought it has nothing to do with my reverse proxy or uwsgi. Actually it was problem with reverse proxy and I could solve my problem by adding following rules to nginx:
proxy_cookie_domain media.$host $host;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header Host $http_host;
proxy_redirect false;