Mailchimp API 3.0 batch/bulk untag - mailchimp

Question

I have a problem with untag the subscribers in a bulk with the Mailchimp API.
In the documentation https://mailchimp.com/developer/guides/how-to-use-tags/#Tag_multiple_contacts_in_bulk is the example:
{
"members_to_remove": [
"john.smith#example.com",
"brad.hudson#example.com"
]
}
Below can you see my PHP code where I with the $methode variable give the value members_to_remove and the $email value is an array with email addresses.
But the script does only add tags with a bulk to the subscriptions instead of remove.
What do I wrong?
public function tag_mailchimp($list_id, $email, $tag, $method) {
$authToken = 'HERE MY KEY';
// The data to send to the API
$postData = array(
$method => $email
);
// Setup cURL
$ch = curl_init('https://us2.api.mailchimp.com/3.0/lists/'.$list_id.'/segments/'.$tag);
curl_setopt_array($ch, array(
CURLOPT_POST => TRUE,
CURLOPT_RETURNTRANSFER => TRUE,
CURLOPT_HTTPHEADER => array(
'Authorization: apikey '.$authToken,
'Content-Type: application/json'
),
CURLOPT_POSTFIELDS => json_encode($postData)
));
// Send the request
$response = curl_exec($ch);
return $response;
}

Answer 1

It works, but I don't know what I do else.., the code:
foreach($members as $member) {
$list[] = $member->email;
}
$Mailer->tag_mailchimp('12345678', $list, 123456, 'members_to_remove');
And in the class I have the next function:
public function tag_mailchimp($list_id, $email, $tag, $method) {
$authToken = 'HERE MY KEY';
// The data to send to the API
$postData = array(
$method => $email
);
// Setup cURL
$ch = curl_init('https://us2.api.mailchimp.com/3.0/lists/'.$list_id.'/segments/'.$tag);
curl_setopt_array($ch, array(
CURLOPT_POST => TRUE,
CURLOPT_RETURNTRANSFER => TRUE,
CURLOPT_HTTPHEADER => array(
'Authorization: apikey '.$authToken,
'Content-Type: application/json'
),
CURLOPT_POSTFIELDS => json_encode($postData)
));
// Send the request
$response = curl_exec($ch);
return $response;
}