Hi,
Thanks for the access.
I just made a test transaction and I got your checkout page with the javascript errors.
It looks like you have some jQuery code in your website but that the jQuery lib is not include every time.
So, because of these errors, the processing of the page is stopped and the javascript in the page content is not executed (which should validate the form and redirect to paypal).
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.