Price Calculations v2.4.1 not working after HikaShop 6.4.1 update

-- HikaShop version -- : 6.4.1
-- Joomla version -- : 6.1.0
-- PHP version -- : 8.4

I hope you can help me. Since updating HikaShop and the Price Calculations plugin, the price calculations on my product pages are no longer working. I am not a developer myself, so I reached out to Claude (AI assistant by Anthropic) for help investigating the issue. I want to be upfront about this — I am not certain whether the findings below are the actual cause, but I wanted to share everything we found so you have as much context as possible.

Environment:
- HikaShop Business: v6.4.1
- Price Calculations plugin: v2.4.1
- Joomla version: 6.1.0

What we found during investigation:

1. The browser console shows the following error on the product page:
"Cannot read properties of null (reading 'price')"
at aluminium-naam-typeplaat/:140
at xhr.onreadystatechange (hikashop.js:1587)

2. The AJAX call to /component/hikashop/calculations/calculate/ returns: "No product id"

3. When inspecting the form element on the product page via the browser console:
- document.getElementById('hikashop_product_form') exists
- However, the form only contains basic cart fields (cart_type, add, ctrl, task, return_url)
- There is no product_id field and no custom fields present in the form
- window.Oby.getFormData() therefore returns no product_id

4. In calculations.php (line 81), the generated JavaScript uses resp.price to read the AJAX response. Based on the changelog of v2.3.0, the response now returns price_value instead of price. I have already updated this line locally as a test, but this did not resolve the issue because the form is empty. After this test I bring everyting back to normal to instal the latets plugin again.

5. The form[name="hikashop_product_form"] appears to no longer contain the product data and custom field values that the plugin relies on. This may be related to a change in HikaShop 6.4.x in how the product form is structured or populated.

Thank you very much for your time and support.

Kind regards,
Lumiga