403 Forbidden

Hello,
I launched a research awards a couple of weeks back and we have just changed our website and host.

The page that used to hold the awards details was:

http://www.childgrowthfoundation.org/default.aspx?page=2018researchawards

This was hosted by a different company so the page doesn’t exist anymore. The awards page is now:

http://childgrowthfoundation.org/2018-research-awards/

I have installed redirection a 301 redirect with the source as the top page above and the target url as the new page.

It hasn’t made any difference, I get a 403…
Forbidden
You don’t have permission to access /default.aspx on this server.

Does anyone know why please?

Thank you

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