contact form issues!

Hi
i have a contact form here: https://valliniskippack.com/contact.html

the form is sending me emails - that works.... but when i click to submit the form it opens a new page here: https://valliniskippack.com/include/sendemail.php

with this:
{ "alert": "success", "message": "We have successfully received your Message and will get Back to you as soon as possible." }

how can i get this to work??

thanks