There will be no current element (NULL) if you don't rewind first.
(PHP 5, PHP 7, PHP 8)
SimpleXMLIterator::rewind — Rewind to the first element
This method rewinds the SimpleXMLIterator to the first element.
This function has no parameters.
No value is returned.
Example #1 Rewind to the first element
<?php
$xmlIterator = new SimpleXMLIterator('<books><book>PHP Basics</book><book>XML Basics</book></books>');
$xmlIterator->rewind();
var_dump($xmlIterator->current());
?>
The above example will output:
object(SimpleXMLIterator)#2 (1) { [0]=> string(10) "PHP Basics" }