Why is my Grand Total not updating after I increase or decrease the quantity in React?-CodePudding

This is a basic application that I am working on using React and Bootstrap. Here, The Grand Total is not changing when I update the quantity. I have attached the Sandbox link. Please let me know the mistake.

CodePudding user response：

the name of your variable is the problem products

const grandTotal = () => {
    let total = 0;
    for (let prd of product) {
      total  = prd.price * prd.quantity;
    }
    console.log(total);
    return total;
  };

products point to this variable

const products = [
  {
    sno: "123",
    name: "Apple Watch",
    price: 290,
    quantity: 2
  },
  {
    sno: "567",
    name: "Samgung Watch",
    price: 278,
    quantity: 5
  },
  {
    sno: "785",
    name: "Cas",
    price: 123,
    quantity: 1
  }
];