Load complete XML with simplexml_load_string

I have an XML that has a parent node Produtos and 2500 child nodes produto , all child nodes have a id key that starts at 1 and goes up to 2500. When I try to load XML using the simplexml_load_string function only 2237 child nodes are "parseted", is there any limit to this function? If so, how can I increase? below code used;

$call = curl_init();

$options = [
    CURLOPT_URL             => $import->xml_path,
    CURLOPT_RETURNTRANSFER  => 1,
    CURLOPT_SSL_VERIFYPEER  => false,
    CURLOPT_CUSTOMREQUEST   => 'GET',
    CURLOPT_CONNECTTIMEOUT  => 20,
    CURLOPT_RETURNTRANSFER  => 1,
    CURLOPT_SSL_VERIFYHOST  => 0,
];

$xml = simplexml_load_string($xmlString, null, LIBXML_NOCDATA);
// => $xml é uma classe SimpleXMLElement com um attributo 'produto' (array) com 2238 indices.