Hello,

What I could suggest here is to use certbot to issue a new SSL certificate for your subdomain and then also let certbot add the redirect to HTTPS automatically for you.

If you have certbot already installed, then you can do that with the following command:

sudo certbot --apache -d gestor.izybai.com -d www.gestor.izybai.com

You should see the following output in the end:

Please choose whether or not to redirect HTTP traffic to HTTPS, removing HTTP access.
-------------------------------------------------------------------------------
1: No redirect - Make no further changes to the webserver configuration.
2: Redirect - Make all requests redirect to secure HTTPS access. Choose this for
new sites, or if you're confident your site works on HTTPS. You can undo this
change by editing your web server's configuration.
-------------------------------------------------------------------------------
Select the appropriate number [1-2] then [enter] (press 'c' to cancel):

If you choose option number 2, then certbot will add the redirect for you.

For more information you can take a look at this tutorial here:

https://www.digitalocean.com/community/tutorials/how-to-secure-apache-with-let-s-encrypt-on-ubuntu-18-04

Hope that this helps!
Regards,
Bobby