Submitting product attributes via Ninja Forms wordpress?

I have a wordpress website selling products. On the product page there is a button “Ask a question”, through which a pop-up form created on the basis of the “Ninja forms” plugin opens. There are fields for input, when they are filled in, a letter is sent to the mail. But the customer wants the attributes of the product (size, material, etc.), through which the user asks the question, to come as well. Attributes are displayed on the product page as a technical description of the product. P.s I use hidden fields in this form to pass the data of the page from which the question was asked. (Url) But I can not pass attributes to these fields, maybe it can be as- what to do? for example, to display attributes for a specific product on a product card, I use the following code:

?php global $product; $product-get_attribute('Condition');?

Maybe there is a possibility to do it somehow in a hidden field? How to do it?