Oh, my mistake!
Now I see 4 fixtures all for current season. What about previus h2h history?

This End point works, it’s just that you look at the example provided in the rapidapi doc and not the return of your request!

In the window from right to top left you have “sample response” which is present as an example and also “your response” which is the result of the past request. The best way to avoid this confusion is to use Postman.