Symfony2 Ajax从一个脚本错误中获取许多请求

I have a very strange problem with my ajax requests. I have a code, that increases the quantity of products by one every time I press a button. The code kinda works but I have a problem. When I press the button I am not getting one request, but 4 at the same time! I have no idea how is that even working, but it happens.I have a very strange problem with my ajax requ