performQuickAction for Case.SendEmail requires a parent object errorCode: MISSING_ARGUMENT Exception in Salesforce

The following exception occurs when SendEmail from Case object is used and contextId is not passed. To resolve the issue, please add contextId to the POST body.

message: performQuickAction for Case.SendEmail requires a parent object
errorCode: MISSING_ARGUMENT

Sample Code with contextId:
{    
    "contextId": "5008c00001Ejue0AAB"
    "record": {
        "HtmlBody": "<div+style=\"font-family:+Arial;+font-size:+14px;\">Test</div>",
        "Subject": "InfallibleTechie",
        "ToIds": ["0038c00002bkSPZAA2"]
    }
}