using zoho books API for retainer invoice in zapier

using zoho books API for retainer invoice in zapier

hello, I have to create a retainer invoice when a estimate is accepted and i got everything set up but I cant seem to figure out what the good format for the api request is for the line items, I dont see what im doing wrong can someone help me with this ?

{
    "result": {
        "request": {
            "method": "POST",
            "url": "https://www.zohoapis.com/books/v3/retainerinvoices?line_items=[{\"description\":\"Dépots de 25% pour votre déclaration de revenus\",\"rate\":373.67}]&customer_id=xxxxxxxxx&organization_id=xxxxxxx&payment_options=\"payment_gateways\":[{\"configured\":true,\"additional_field1\":\"standard\",\"gateway_name\":\"stripe\"}]&reference_number=2023",
            "querystring": null,
            "headers": {},
            "body": "",
            "data": null
        },
        "response": {
            "status": 400,
            "headers": {},
            "body": "{\"code\":4,\"message\":\"Invalid value passed for JSONString\"}",
            "data": {
                "code": 4,
                "message": "Invalid value passed for JSONString"
            }
        }
    }
}

pretty sure its a formating issue but cant find what is wrong with the request