Update children of a page in a loop ends in error (nesting level too deep)

The CMS Questions
1

I need to update the children of a page in a loop, but this ends in an error.

“Nesting level too deep - recursive dependency?”
on the line 928: array_multisort(…$params); in the file kirby/src/Toolkit/Collection.php

<?php
$contentpage=page("our-catalogue/antique-maps");     	
foreach($contentpage->children()->listed() as $pg){
	$pg->update([
		'webprice' => "newprice"
	]);
}
?>

// yml of the parent page

sections:  
  pages:
    type: pages
    layout: list 
    templates: 
      - category-item
2

How are these pages sorted? By date or by number?

3

They are sorted by number.

4

Are there any. duplicate numbers maybe?

How many pages are there in the loop?

5

There are no duplicate numbers. There were 100 items, but when i reduce to 5 items, there still is the error. What could cause this type of error?

6

Could you send me your project or a stripped down version of it for testing? I can’t reproduce the error in a Starterkit.