gateway passed as 1 Razorpay still shows as manual in the order

I am using the shopify rest api to create a draft order and then completing it with payment_pending set to true
after that i am trying to add a transaction using the /transactions.json endpoint where i am passing the gateway as “1 Razorpay” but still it shows as gateway manual in the UI

{
    "transaction": {
        "currency": "INR",
        "amount": "60.18",
        "kind": "sale",
        "gateway": "1 Razorpay",
        "payment_id": "",
        "test": true,
        "authorization": "",
        "status": "success",
        "parent_id": "7616395116844"
    }
}

what am i doing wrong here ? Razorpay is properly setup as a gateway in my store, when i use it to buy something directly from the webite, in admin dashboard the order shows gateway as 1 Razorpay correctly

I am a developer, just guide me in the right direction