I take it from your example and by testing it that the problem you are encountering is that the user is not redirected at all. Do you have any redirect commands in your .htaccess file that are working? If you have a shared host, you may not be able to set .htaccess commands on your server.

I have used redirects with dynamic content and have not run into problems under Apache, and your syntax looks to be correct to me.

If you are able to use .htaccess commands and have other redirects that work, check the error log for your server to see if the software is encountering an error when trying to run the redirection command.

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