It is solved from the reference URL- https://community.hubspot.com/t5/APIs-Integrations/Webhook-JSON-Understanding-Extracting-Data/td-p/226257
I have used the code -
$json = file_get_contents(‘php://input’);
// Converts it into a PHP object
$json = json_decode($json, true);
//get lastname, firstname, email from array
if(is_array($json)){
$lastname = $json[‘properties’][‘lastname’][‘value’];
$firstname = $json[‘properties’][‘firstname’][‘value’];
$mobilephone = $json[‘properties’][‘mobilephone’][‘value’];
$email = $json[‘properties’][‘email’][‘value’];
$vid = $json[‘vid’]; // vid; contact specific identifier
}
and got the solution