.htaccess - rewrite rule does not rewrite url as expected

I have a problem with a CMS website, that normally generates readable urls. Sometimes it happens that navigation links are shown as www.domain.com/22, which results in an error, instead of www.domain.com/contact. I have not found a solution for this yet, but the page is working if the url is www.domain.com/index.php?id=22.

Therefore, I'm trying to rewrite www.domain.com/22 to www.domain.com/index.php?id=22 and I have used this rewrite rule:

RewriteRule ^([1-9][0-9]*)$ index.php?id=$1 [NC]

I tested it using http://htaccess.madewithlove.be and here it shows the correct result, but on the website no rewrite is happening.

Begin: Rewrite stuff

RewriteEngine On

RewriteRule ^(typo3|t3lib|tslib|fileadmin|typo3conf|typo3temp|uploads|showpic.php|favicon.ico)/ - [L]

RewriteRule ^typo3$ typo3/index_re.php [L]

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-l

RewriteRule .* index.php [L]

Options +FollowSymLinks

RewriteCond %{HTTP_HOST} ^domain.dk$ [OR]
RewriteCond %{HTTP_HOST} ^www.domain-alias.com$
RewriteRule (.*) http://www.domain.com/$1 [R=301,L]

RewriteRule ^([1-9][0-9]*)$ index.php?id=$1 [NC]

End: Rewrite stuff