Getting content is not valid for use with single send API

trying to send the following object
{
“emailId”: 6760xxxxxx,
“message”: {
“to”: “jain_ayushxxx94@yahoo.com”
},
“contactProperties”: [
{
“name”: “FirstName”,
“value”: “Ayush”
}

]

}

using postman on following link
https://api.hubapi.com/email/public/v1/singleEmail/send?hapikey=aexxxxxxxx

i get following error:
{
“status”: “error”,
“message”: “Content is not valid for use with single send API. Requires subcategory ‘single_send_api’”,
“correlationId”: “63d3144b-6457-4709-8e3d-f73e87bc53d3”,
“sendResult”: “MISSING_REQUIRED_PARAMETER”,
“requestId”: “83d36405addf8a54c4e946654e8c0f9d”
}

can please help me resolve this error.

Hi @akash_gupta, You’ll need to make sure that the email has been saved for use with the single-send API, and not saved for automation or manually sent.

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