Custom functions help (Again)

Custom functions help (Again)

Can you tell me what I'm doing wrong with custom functions here please :-( .....

itemID = item.get("item_id").toString();
orgID = organization.get("organization_id").toString();
customfields = item.get("custom_fields").toList();
item = item.get("name");
var data = {
"name" : "TelBots Test",
"rate" : 5,
"custom_fields" : [{
"index" : 3,
"value" : "XyXyX"
}
]};
response = zoho.books.createRecord("items", data);
info response;

And if you would be so kind as to show me how to update a customer shipping_address:address I'd be extremely grateful :-)

I'm learning slowly with Zoho tech guys help - Thank You :-)