Redirect of ?page_id=xxxx not working

FAO Micheal Davis
As requested – you can login to see the issue for yourself.

I used to have a page at:
https://whitenoisetouring.com/?page_id=3209
Which was my work availability calendar.
It now resides at:
https://whitenoisetouring.com/index.php/calendar

As per the advice from the other support ticket, I’m using a plugin called ‘MyCustomFunctions’ to add the following code to the functions.php file, just for ease.

/**
* Disable appending the query string in the redirection URL.
*
* @param int $number
*/
add_filter( ‘rank_math/redirection/add_query_string’, ‘__return_false’ );

There are other redirects that I need to enable too – but the calendar page is the main one.
I can get an OVERALL redirect working if I change the Fallback Behaviour to “Redirect to Homepage” – but obviously that’s not what I need.

Thank you in advance.
Cliff.