The rule in .htaccess does not work (CNC settings). Why?

Question

htaccess

I'm trying to make it so that when you enter the following in the address bar:
site.ru/78
There was a redirect to
site.ru/folder/handler.php?id=78
Here's what I write in .htaccess at the root of the site (DOES NOT WORK):
RewriteEngine On
RewriteBase /
RewriteRule ^([0-9]+)$ folder/handler.php?id=$1 [L]
Help with advice.

Answer 1

RewriteRule ^([0-9]{.+})$ folder/handler.php\?id=$1 [L]