How to check for duplicates in amocrm?

Question

API

Hello!
Can you please tell me how to check for duplicates in amocrm by phone number before creating a new deal? I'm using the dotzero client: https://github.com/dotzero/amocrm-php
Trying this but it doesn't work:
$searchContactPhone = $_POST['phoneInput'];
$existsContact = $amo->contact->apiList([
'query' => $searchContactPhone,
'limit_rows' => 1
]);
if ($existsContact == $searchContactPhone) {
$contact = $amo->contact;
$contact['phone'] = $searchContactPhone;
$contact->apiUpdate((int)$id, 'now');
$contact->addCustomField(245689, $searchContactPhone, 'WORK');
}