nikshi on "[Plugin: PopUp by Supsystic] Wait a long time when press GO (subscribe)"

Hi, I have the following issue:
When I fill the name and email in popup and press GO must wait a long time before show successful message...
You can see the problen here: http://fashionmodebulgaria.com/

Thanks in advance !

https://wordpress.org/plugins/popup-by-supsystic/