Order products not working properly with discount

[techbsol]

Hello,

I've got some problem on an old installation of Prestashop (1.5.6.0) with the products ordering.

 

If I search for something and ask Prestashop to sort the results by Price, the system considers only the original price of those products and not the discount applied. For example, I have those products:

A > Original Price: 2 520,00€, no discount, Final Price: 2 520,00€
B > Originale Price: 3 920,00 €, no discount, Final Price: 3 920,00 €
C > Original Price: 4 053,27 €, -45% discount, Final Price: 2 229,30 €

 

Now, I expect those products to be ordered like this (using Price "From lowest"): C, A, B.
Instead, they are sorted like this: A, B, C.

Even if I use the Price "From highest", they get sorted like this: C, B, A.

Basically, it seems that Prestashop won't consider the discount applied on the product "C" when sorting the search results.

 

Is there any way to solve this?

Thanks a lot.