Hello Fahad.
I am facing the same issue as well I guess
here is my URL to add in cart
xyz.com/cart/?add-to-cart=883&variation_id=985&attribute_packages=pro
in backend my attributes are Free | Pro
this was working fine till now but after updating 3.0.8 its not working.
I guess its case sensitive Issue as i can see following url with capitle ‘P’ works fine
xyz.com/cart/?add-to-cart=883&variation_id=985&attribute_packages=Pro
I dont find any solution to this yet and as we have more then 500 products i can change the atribute values ??
any thoughts in this ?