Server Script Error

Have a simple Server script where I am sending Name of customer and Phone Number in as below.

    "customer": "Nitin",
    "phone": "+915555555555"

It’s working fine on my local environment. But not running for Frappe Cloud.

It gives following error.

“exception”: “json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)”,

What should be the issue?