When I created a new form. Before I paste the code on a certain page it has automatically added into all the pages which were already active. Only this form was showed up other all the contents gone. Even after uninstallation, I could solve it. I was not able to even add new pages or posts. On every page, this was the error I got
"[smartpay_form id="2" behavior="embedded" label=""]" I have completely disappointed for buying this plugin.