Back in Stock App - Form Submitting Null Values on Collection Page

[fitneshmaniaapp]

Hi, I'm developing a Back in Stock app and have added a "Notify Me" button under out-of-stock products on the collection page. When the button is clicked, a form opens correctly, displaying the product title and variants properly.

However, the issue is that when submitting the form, product ID and variant ID are empty (null). The form fields appear to be correct, but they don't retain the data on submission.

Has anyone faced a similar issue or knows how to properly pass product data from the collection page to the form submission? Any help would be greatly appreciated!