My users are getting wrong shipping prices/zones

-- url of the page with the problem -- : 222publications.com/newcatalog/en
-- HikaShop version -- : 2.3.0
-- Joomla version -- : 2.5.16
-- PHP version -- : 5.3.28
-- Browser(s) name and version -- : CHROME

Hello Everyone,

I've been using HikaShop for about a year or so now and recently, my users are reporting a strange thing which has never happened before.

My users are getting the wrong postage (shipping) price and zones comparing to the country they have selected for their billing/shipping. I have no idea why this is happening. For example. Recently one of my Australian Customers made an order and the shipping zone given to him was Zone 5 (Ireland) instead of Zone 12 (Australia). He made the exact same order 15 minutes later and then the correct zone was selected for him (Zone 12). I don't know how to resolve this issue but I know that I'm losing some customers because of this. Please help me out with this. Thanks in advance.

Hello,
Can you give me more information about what do you exactly mean by :

the shipping zone given to him was Zone 5 (Ireland) instead of Zone 12 (Australia)

Dear Mohamed,

I've implemented different shipping zones based on the weight of the products we sell and based on the countries our customers make their order from. This particular customer is from Australia and based on my calculations, Australia is placed in our Zone 12. Our Zone 5 has only Ireland in it. You have to know that our Shipping zones and prices are calculated automatically. So there's no way this customer could have selected Zone 5 for his order since his address is in Australia. That's why I'm confused about this. Even though the system chooses the zone and shipping price for the order based on the billing address and book weight, we're still facing this issue and the wrong shipping zone and price has been selected for him.

Our customer made the same exact order about 15 minutes later but this time, everything was chosen correctly and according to the system. I don't know where the problem is being generated from. Can you please help me?

About the update, unfortunately I don't have my subscription anymore. If I absolutely have to do that, I will find a way to pay again. But I have to be sure that's the only option.

Dear Jerome,

The users don't select the shipping zone or shipping price. The system automatically calculates it for them and selects the right zone and price for them based on their order..