$groupsApi = (new MailerLiteApi\MailerLite("72d3647bab652739bc4577f1fe9dfb24"))->groups();
$subscriber = [
'email' => 'john@example.com',
'fields' => [
'name' => 'John',
'last_name' => 'Doe',
'company' => 'John Doe Co.'
]
];
$response = $groupsApi->addSubscriber(GROUP_ID, $subscriber); // Change GROUP_ID with ID of group you want to add subscriber to
