Redirection does not work

I use CM Tooltip Glossary (and Encyclopedia type of custom posts type).
Now I have a situation that I use them wrong.
So I want to change this custom posts type to normal posts using Post Type Switcher.
I am trying to use Redirections in the Rank Math plugin, but it does not accept/save the redicection.

What do I do:
1. Copy the complete link of the glossary page I want to change to a posts.
2. Change a glossary posts (link called ifrsdefinition) to posts
3. Use Add Redirections:
Source URLs: https://www.faqifrs.com/ifrsdefinition/simplified-approach-lifetime-expected-credit-losses/
Destination URL: https://www.faqifrs.com/simplified-approach-lifetime-expected-credit-losses/
Redirection type 301 Permanent Move
Status: Active
4. Press Add Redirection

And I return to the Redirections page without a redirection being added.

Please let me know if what I am trying is wrong (not possible in Rank Math) or suggest how I should do this.

Many thanks in advance

Henk Oonk