Add Emails to Recipient Group

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL,"https://insprl.com/api/email/recipient-groups/add-emails");
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_HTTPHEADER, 
   array( 'Authorization: {CLIENT_KEY}'
));
curl_setopt($ch, CURLOPT_POSTFIELDS, 
http_build_query(
array(
   'client_id'	=> '{CLIENT_ID}',
   'groupslug'	=> "valuable-customers",
   'emails'	=> '[{"email":"customer1@example.com","first_name":"Rohan","last_name":"Gupta","city":"Bangalore"},{"email":"customer2@example.com","first_name":"Deepa","last_name":"Soni","city":"Mumbai"}]',
)
));
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$response = curl_exec($ch);
curl_close ($ch);

{
"code":"100",
"message":"success",
"data":{
   "status":"added",
   "msg":"Added 2 new email(s) data successfully"
}
}