Hello,
I'm working with TYPO3 v13.4.15 and using the extensions:

• extcode/cart
• extcode/cart-products

I followed the official tutorial to set everything up.
However, when I try to add a product to the cart, I encounter the following error:

Core: Exception handler (WEB): Uncaught TYPO3 Exception: Call to a member function getUid() on null Error thrown in file /var/www/html/vendor/extcode/cart-products/Classes/Controller/ProductController.php in line 327. Requested URL: https://website.ddev.site/produkte/detail.html?tx_cart_cart%5Baction%5D=add&tx_cart_cart%5Bcontroller%5D=Cart%5CProduct&cHash=31934542a2e732a8a848ed38907f060f

To make sure it's not project-specific, I tested the same setup in a different TYPO3 project — but the error still occurs in exactly the same way.

Steps to reproduce:

1. Install TYPO3 v13.4.15
2. Install and configure extcode/cart and extcode/cart-products using the tutorial
3. Open the detail page of a product
4. Try to add the product to the cart

Expected behavior:

The product should be added to the cart without errors.

Actual behavior:

A fatal error occurs when submitting the add-to-cart action. It seems like a null value is passed where an object is expected in ProductController.php on line 327.

Additional context:

Let me know if you need any further logs or configuration details.
Thanks in advance!