Not redirected to paypal after form submit PRO version

I bought the PRO version to keep track of payments when the form is submitted. When using the PRO version the user is never redirected to paypal to complete payment. Nothing happens when they click the submit button. I can see them in the payments log but they are never redirected to paypal to make the actual payment. I had to revert back to the free version of the plugin for the form to redirect to paypal like it should. I would like a refund for the plugin please since it does not work as it should