why i'm getting 400 (Bad Request)

why i'm getting 400 (Bad Request)

Good day,

i'm trying to get my invoices list using zoho books api

i was able to get my bills but when i try to do the same for 
invoices i get back {code: 2, message: "The request passed is not valid."}

here is my code:
url = "https://books.zoho.com/api/v3/invoices?organization_id=XXXXXXXXX"
fetch(url, { method: 'Get', headers:{"Content-type": "application/x-www-form-urlencoded;charset=UTF-8", "Authorization": `Zoho-oauthtoken ${token}`} })

i don't see what am i doing wrong it should work?

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