Zoho Books API

Hello,

I'm trying to use the geturl function in Zoho Creator for Zoho Books:

X = input.Invoice_ID.toString();

headerMap = Map:String({"Authorization":"Zoho-authtoken <CODE>"});

x = getUrl(" https://books.zoho.com/api/v3/invoices/" + X + "?organization_id=452140211",headerMap);

As a response I get:

{"code":2,"message":"Invalid value passed for organization_id"}

What am I doing wrong?