I have created a Sub-Total basket here:

Sub-Total app on Codepen

Everything works fine except of Ajax submit form and the end of my jQuery code.

I want that by clicking on the submit button an alert box appears which shows the values of the form as JSON. 

The alert box should show Something like this:

{"items":[{"name":"Cotton T-Shirt, Medium","price":"1.99","cost":"1.99"},{"name":"Baseball Cap, One Size","price":"2.99","cost":"2.99"},{"name":"Swim Shorts, Medium","price":"3.99","cost":"3.99"}],"subtotal":8.97,"total":10.764000000000001,"tax":1.7940000000000003}

I tried everything but the alert box is now showing.

On codepen however, a click of submit direct me to a page which shows me the last set of the JSON but not all 3 sets.

Could you please help to find my mistake?

Why the alert box doesn't come up? 

Thanks