form now working in static front page

HI,
I am developing a WordPress site .
The link is : https://www.desiznstudio.com/paul/test/

I have used Rainmaker plugin to create form for email subscription.
In the site I have used to different forms, one in header and footer and another is in sidebar.

The problem is that in the home page ( which is a static front page) both header and footer forms are not working. Once filled up info and submit they will redirect to a 404 page without submitting the form info to admin panel.

Please check this link : after using the header form in home page or front page:

https://www.desiznstudio.com/paul/test/?name=aaa&email=abcd%40123.com&button=Cliquez+ici+pour+valider%21#rainmaker_form_77

But if we go any inner page then all the forms works fine.
Please solved this problem.

I need one more thing. All I want to keep the user in same page after submitting the form . In this case what will be the redirection URL so user will be in same page but formwill be refreshed and work properly.

My email: jack.expertdesigner@gmail.com

Thanks