Getting must be valid amount response message from Affirm

[sandeep18051989]

I am working on an Affirm payment method integration. Sending checkut object to Affirm, but getting an error message:
{
"status_code": 400,
"type": "invalid_request",
"message": "Invalid Request: Must be valid Amount"
}

Given below is the checkout object I am sending with public API key as well:
{
"merchant": {
"user_confirmation_url": "http://localhost/Able9B6750Test3/Affirm/Confirm",
"user_cancel_url": "http://localhost/Able9B6750Test3/Checkout/Payment",
"public_api_key": "ABCDEFGHI",
"user_confirmation_url_action": "GET",
"name": "W2M.Affirm"
},
"shipping": {
"name": {
"first": "Market",
"last": "aa"
},
"address": {
"line1": "5628 W 120TH ST",
"line2": "",
"city": "ALSIP",
"state": "IL",
"zipcode": "60803-3410",
"country": "United States"
},
"phone_number": "1-888-128-3772",
"email": "admin@gmail.com"
},
"billing": {
"name": {
"first": "Web2Market",
"last": "Web2Market"
},
"address": {
"line1": "5628 W 120TH ST",
"line2": "",
"city": "ALSIP",
"state": "IL",
"zipcode": "60803-2210",
"country": "United States"
},
"phone_number": "1-888-968-3772",
"email": "skumar@web2market.com"
},
"items": [
{
"display_name": "Prima Chain Lock (66", Heavy Duty); Universal",
"sku": "0300-0103 ",
"unit_price": 101,
"qty": 1,
"item_image_url": "http://localhost/Able9B6750Test3/Assets/ProductImages/0300-0103.jpg",
"item_url": "http://localhost/Able9B6750Test3/Abandoned-Products/Prima-Chain-Lock-66-Heavy-Duty-Universal",
"categories": [
[
"Springs"
]
]
}
],
"discounts": null,
"metadata": {
"shipping_type": "Free Shipping",
"mode": "redirect"
},
"order_id": "6260588",
"currency": "USD",
"financing_program": "",
"shipping_amount": 0,
"tax_amount": 10,
"total": 111
}

Also, checkout oubject is being build while I am on payment page and it has orderID and OrderNumber required. But, Order is not yet generated on my ecommerce website. What should I do ?