Crash at check in the cart, and in backend - edit product

-- url of the page with the problem -- : ferrecant.com
-- HikaShop version -- : 2.6.3
-- Joomla version -- : 3.9.9
-- PHP version -- : 7.2
-- Error-message(debug-mod must be tuned on) -- : Warning: Illegal string offset 'state_A_Coru__a_3499' in /home/ferrecant/public_html/administrator/components/com_hikashop/classes/field.php on line 645

Recoverable fatal error: Object of class stdClass could not be converted to string in /home/ferrecant/public_html/administrator/components/com_hikashop/classes/field.php on line 645

I have a crash on my web when i try to do a purchase, i have error 500.
This is showed when i do the try:

Warning: Illegal string offset 'state_A_Coru__a_3499' in /home/ferrecant/public_html/administrator/components/com_hikashop/classes/field.php on line 645

Recoverable fatal error: Object of class stdClass could not be converted to string in /home/ferrecant/public_html/administrator/components/com_hikashop/classes/field.php on line 645

i have the same problem in the backend, if i want to edit a product or pretend to export for do a save copy.

can you help me? Thanks!


the url is: www.ferrecant.com
and the problem crash when you look at your cart and you click "siguiente" (next)

Hi i need a solution, sorry because the fast and my english

Hello,

Hikashop 2.6.3 isn't compatible with PHP 7.X, so the potential solutions will be to :
- Update your Hikashop version

OR

- Use PHP 5.X

Kind regards,
Mohamed Thelji.