Why does a 504 error occur when updating a record in the database?

Question

PHP

Hello.
I'm trying to update in a database write cycle in a Laravel project. The code is as follows:
for ($i = 0; $i <= (count($replace)-1); $i++) {
$edit_art = Article::find(97 + $i);
$edit_art->article = $replace[$i];
$edit_art->update();
}
This causes a "504 Gateway Time-out" error, and no entries are updated.
What could be the reason?