Notify Me not working with Custom field and Child Products!

[Hamid777]

Hello

VirtueMart 2.6.17

I have configuration set to show "Notify me" instead of add to cart for out of stock products, and parent/child products using the stockable variant plugin. For products which are out of stock is working perfect but for child products which has quantity not working properly.
in this case when i click on add to cart button i get message that the product is out of stock ! but actually child products have quantity. i understood when i click on addtocart button, the button reads quantity of parent which is 0!
How can i solve this problem? please help me.

Regards 

[Hamid777]

I solved this problem, 6 hours works on this problem and codes and what a crazy solution!
Just should give 1 quantity to parent product and it works!