Cuando abro mi página me dice que no es seguro, pero me enviaron esto desde donde compré el dominio.
Este certificado SSL es completamente gratuito porque está asociado a un dominio registrado en Hostalia y está siendo utilizado con el producto Plan Dominio*.
The SSL certificate probably works with their host, but not with ours (check if they didn’t offer you a hosting plan as well). SSL certificates are sent from origin server, not from DNS server.
Our servers do provide SSL cerficates however they are issued only for free *.000webhostapp.com domains (which is why you encounter that warning screen).
In order to avoid this issue, I suggest you to link your domain with Cloudflare to make use of their free SSL feature: