session Storage remove Item javascript problem

Solved Now - sessionStorage->array->make New Array without item -> back to sessionStorage

This is driving me nuts, and yes have looked all day for a solution.

I'm trying to remove item from the sessionStorage. But just one item. I can find the item, just can't remove it. Any help would be great, Thanks

function removeCartItem(key) {
    if (sessionStorage.getItem('shopping-cart')) {
        var IsItemThere = false;
        var shoppingCart = JSON.parse(sessionStorage.getItem('shopping-cart'));
        shoppingCart.forEach(function(item) {
            var cartItem = JSON.parse(item);
            if(cartItem.key === key){
                IsItemThere = true;
            }
        });
        if(IsItemThere == true){
            var cartArray = new Array();
            shoppingCart.forEach(function(item) {
                var cartItem = JSON.parse(item);
                if(cartItem.key != key){
                    cartItem = {
                        key: cartItem.key,
                        id: cartItem.id,
                        productName: cartItem.productName,
                        price: cartItem.price,
                        quantity: cartItem.quantity
                    };
                    var cartItemJSON = JSON.stringify(cartItem);
                    cartArray.push(cartItemJSON);
                }
            });
        }
        sessionStorage.removeItem('shopping-cart');
        var cartJSON = JSON.stringify(cartArray);
        sessionStorage.setItem('shopping-cart', cartJSON);
    }
}

This is how each item look like, and yes, the alert does popup {"key":14759,"id":"1","productName":"Sample Product 1","price":"12.77","quantity":"1"}