Cannot add products, plus or minus numbers of product in cart, cannot checkout.

[kentcheung2000]

My website is as followed:

http://civicmart.com/cfj/

I cannot add products, plus or minus numbers of product in cart, cannot checkout.  Spend hours to try to look into it...How can I fix it....Many thanks.

php version 5.6, Joomla 2.5, virtuemart 3.0.18

[Ghost]

You have two instances of jQuery loaded.

[kentcheung2000]

Thank you for your reply.  How do I disable the one jQuery and which one do I keep?  Where is it located?.. Many thanks.

[GJC Web Design]

impossible to say from just the front end

one is the normal J3 jui.. the other is external   //ajax.googleapis.com/ajax/libs/jquery/1.8/jquery.min.js

check your (poorly coded)  extensions