PayPal checkout 500 error - '0 Cannot unset string offset'

-- HikaShop version -- : 5.0.4
-- Joomla version -- : 3.10.12
-- PHP version -- : 7.4.33
-- Browser(s) name and version -- : Opera
-- Error-message(debug-mod must be tuned on) -- : 500 error - '0 Cannot unset string offset'

Hi,
the above error is happening starting from this week 13/4. We are on an old version of Joomla while preparing a new J4 based site. However, the site has been operating without issue up until this occurred. The is product is definitely in stock.

Let us know what addition information or access you need.

Ian and Stu

Hi,

I'm not clear on the situation.
Is the screenshot linked with PayPal Checkout ?
The screenshot seems to come from the URL of a product details page with its product not available.
But you're talking about a problem with PayPal Checkout, and the URL you provided is the one at the end of the checkout process.
Did you provide the wrong screenshot maybe ?
I also tried to look at your checkout, but I can't access your website from where I am: i.imgur.com/tfx3hH5.png
In your message, you're saying " 500 error ", but I don't see this at the top of the screenshot. Do you see that it is a 500 error from somewhere else ?
Normally, when you have a 500 error on a page, you need to activate the "debug" setting of the Joomla configuration and reproduce the issue. That way, you get the full error message with the call stack, and this will allow us to understand where the problem is.
Are you able to try this ?

Hi,
It displays the 500 error page regardless of the product and everything is fine until it goes to the PayPal page.
The attached error is from the browser when I tried another product that is in shock from:
Index.php/categories-listing/checkout
confirm

Thanks,
Ian and stu

I've unblocked France and turned on debugging.

Ian

Hi,

I think you have a problem with your template's error message.
Because that's note what the error page should look like.
Try renaming the file templates/YOUR_TEMPLATE/error.php to something else via FTP in order to use the default error page of Joomla.
Then, activate the "debug" setting of the Joomla configuration page.
Then, try again. You should get the normal error message with useful information on what the problem is.

Hi,
I done that and get the attached error page after trying to pay by credit card (paypal managed).
Can you take a quick look and let me know if we should just roll back.

Thanks,
Ian and Stu

Hi,

Thanks. I've made a patch for this. Download again the install package of HikaShop 5.0.4 on our website and install it on yours and you'll get the patch.

Tested and working!

Thanks for the prompt assistance and resolution (as always).

Kind regards,
Ian and Stu