Redirect with a query var

We are switching from one affiliate platform to another and need to redirect our affiliate query vars.

I tried this:
SOURCE
https://rubnrestore.com?aff=1

TARGET
https://rubnrestore.com?rnr=1

Here’s a screenshot: https://www.webpagescreenshot.info/#v2=e8TKnQuKD

When I create that redirection it removes the query var from the source url.

Thanks