Issue Redirecting a Domain to Another Domain (SSL)

Greetings.

I have an issue with two of my domain names and I would like to know if somebody could be kind enough to try to help me.

I own two domain names I bought from OVH, nibelungen.games and nibelungen.ovh, and the second one also have a hosting service attached to it. What I want to do is to be able to redirect the http/https web requests from (www.)nibelungen.games to (www.)nibelungen.ovh, nothing more, nothing less.

I managed to do it by adding an invisible redirection from (www.)nibelungen.games to https://nibelungen.ovh (please check the attached images to see the redirection records). Everything seems to work fine this way but there's an issue : I can only be redirected in non secure mode.

If I type (www.)nibelungen.games on my web browser, I'm taken to http://(www.)nibelungen.ovh and I have the "non secure connection" warning. If I try to force https://(www.)nibelungen.games, I got an error page saying "www.nibelungen.games doesn't allow the connection".

But when I manually type http(s)://(www.)nibelungen.ovh, I'm good and the connection is secured. Since I've validated and activated a SSL certificate on my nibelungen.ovh domain (please check the attached images to verify this) I really don't know what I have to do now.

Do I have to activate SSL on (www.)nibelungen.games too ? If so, how can I do that since I don't have any hosting service attached to this domain name ? The weirdest thing is that everything were working fine and was totally secured when I was redirecting nibelungen.game to another domain name hosted on a website hosting service competitor...

So, I think there might have an error here on OVH regarding my configuration of nibelungen.ovh and I would like to know which one.

Thank you very much for reading.

Regards.