Quantity issue

I have an issue on products quantity added to cart.
On general settings i have set to “NO” “Show plus/minus button”. Then, on products tab “Allow the customer can change the quantity of each product” is checked. Also “Add separately”.
Does not matter how many quantity i selected on product page it only loads 1 of each related products to cart.
My theme has an ajax cart, don’t know if that’s part of the problem.

Thanks!