Canada Post - Postal Code formatting breaks shipping rates

-- url of the page with the problem -- : www.habbyjacks.com
-- HikaShop version -- : 3.4
-- Joomla version -- : 3.8.7

When I type in a postal code like:
- V1T3K4 the shipping module works fine.

If I mistype the postal code like:
- V1T 3K3 (which is a common Canadian postal code format) then shipping indicates: Free Shipping.

How can this module be configured to accept only the one format that works?

Thanks.

Hi,

You want to edit the post code custom field via the menu Display>Custom fields and use the "regular expression check" field to restrict what can be entered as post code.
For example:

I am using the following for my regular expression check.

(^[ABCEGHJKLMNPRSTVXY]\d[ABCEGHJKLMNPRSTVWXYZ]?\d[ABCEGHJKLMNPRSTVWXYZ]\d$)|(^\d{5}(-\d{4})?$)

This permits Canadian Postal Codes without the space and American Postal Codes.

- If a purchaser enters an invalid postal code (ie: X1X 1X1) which is supposed to be Canada Post's format but doesn't work with the Canada Post plugin, then they receive a custom error message, however they are STILL PERMITTED to continue with the purchase which indicates Free Canada Post shipping.

It looks like I need a way to prevent the user from entering the incorrect Postal Code format at the time they are entering it, or somehow convert it to the correct format.

Hi,

I'm not able to reproduce the issue on your website.
When I try to enter a new address with a wrong post code, the creation of the address is refused, I get an error message, and I can't go to the next step:
monosnap.com/file/UHBjbTsg4dOOXKkbWlK6tJOW3sU3mn