There is a error after upgrade

-- url of the page with the problem -- : www.pianyifa.com
-- HikaShop version -- : 4.3.0
-- Joomla version -- : 3.9.15
-- PHP version -- : 7.4.5
-- Error-message(debug-mod must be tuned on) -- : 0 - syntax error, unexpected 'if' (T_IF)

Today I upgraded hikashop to 4.3.0. Unfortunately there was a error when click add to cart button after upgraded.
Error info:
0 - syntax error, unexpected 'if' (T_IF)

What is the problem? Thanks!

0 - syntax error, unexpected 'if' (T_IF)
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syntax error, unexpected 'if' (T_IF)

Many thanks!
I turned off the "add to cart legacy" and "Checkout legacy".It worked.

error_log.txt[ I have the same problem. flowers.vi When adding an item to the cart trying to check out. syntax error, unexpected 'if' (T_IF) This started after upgrading to HikaShop Business: 4.3.0 Joomla Version: 3.9.18 PHP version 7.3 This is urgent!!!!! Please help!!!![attachment=49302]error_log.txt[
I have the same problem.
flowers.vi
When adding an item to the cart trying to check out.
syntax error, unexpected 'if' (T_IF)

This started after upgrading to HikaShop Business: 4.3.0
Joomla Version: 3.9.18
PHP version 7.3

This is urgent!!!!!

Please help!!!!