ERR_CONNECTION_CLOSED - Django admin site (with Apache)

I am trying to use HTTPS with a Django admin site. I am using SSLIfy Admin Middleware and added the following piece of code to settings.py -

MIDDLEWARE_CLASSES = ('sslifyadmin.middleware.SSLifyAdminMiddleware',..... )

SSLIFY_DISABLE = True
SSLIFY_ADMIN_DISABLE = True

SESSION_COOKIE_SECURE = True  #true means browsers may ensure that the cookie is only sent under an HTTPS conn
CSRF_COOKIE_SECURE = True
SESSION_COOKIE_HTTPONLY = True

SECURE_SSL_REDIRECT = True
SECURE_HSTS_SECONDS = 2592000
SECURE_HSTS_INCLUDE_SUBDOMAINS = True
SECURE_FRAME_DENY = True
SECURE_CONTENT_TYPE_NOSNIFF = True
SECURE_BROWSER_XSS_FILTER = True
SECURE_PROXY_SSL_HEADER = ('HTTP_X_FORWARDED_PROTO', 'https')
SSLIFY_ADMIN_NAMESPACE = "admin"

      

        
        
        
      

    

When I try to open the site. I have encountered the error below -

The web page at https: // (LocalH 8000) / admin / may be temporarily disabled or it may be moved to a new web address. Error code: ERR_CONNECTION_CLOSED

I'm not sure where this is going. I am using it with Apache and installed SSL which came with Apache setup. ( How to enable HTTPS for Apache on localhost? )

Can anyone please help? Thank you in advance.