Sikita,
As mentioned through email and your paypal dispute, please close the dispute and use the Request Refund link at the bottom of any page. We'll gladly refund the purchase for you.
The JFBConnect extension is what you're looking for with Facebook and Google+ integration and it has a slightly higher price over LinkedIn, so we can't just switch your purchase. Once your refund request is submitted and the PayPal dispute is closed, your refund should be processed in just a few hours.
Thanks,
Alex