Sort by Product Price is Not working?

[kalanithi]

All product category,Product Name,Brand Name,Featured Product are sorted is working fine..
I have searched Product Price Not working??? how to solve? please check this my screenshot, please tell me ??

I've searched for this but can't find the answer, can a shopper sort by price in Virtue-mart 3.0.6.2??


Jooomla 3.4.0
Virtuemart 3.0.6.2
Php 5.3.28
Mysql 5.5