The problem with sending SMS by Textlocal.com

Question

I try to use the below example of sending sms by Textlocal.com:

$apiKey = urlencode('Your apiKey');

$numbers = array('123456789');
$sender = urlencode('TXTLCL');
$message = rawurlencode('This is your message');

$numbers = implode(',', $numbers);

$data = array('apikey' => $apiKey, 'numbers' => $numbers, "sender" => $sender, "message" => $message);

$ch = curl_init('https://api.textlocal.in/send/');
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$response = curl_exec($ch);
curl_close($ch);

echo $response;

I always receive the error:

{"errors":[{"code":3,"message":"Invalid login details"}],"status":"failure"}

Link to the documentation: https://api.textlocal.in/docs/sendsms

Does anyone have a solution to the problem ?