PayPal Standard open orders problem

I have two cs-cart ultimate 3.0.6 shops (one is clean install) running on xampp. And one 3.0.6 ultimate on virtual private server. On each of them on successful PayPal payment all orders status are still “Open”. I am using PayPal sandbox account. I even tried my real PayPal account with shop on virtual private server without success.

I have already applied patch from this post

My shop main currency match currency in PayPal settings

email address in cs-cart PayPal settings match primary email in PayPal account

PayPal settings is set according to cs-cart kb

cURL ir enabled

tried to dissable SEO

play with htaccess

nothing helps. I would appreciate any help