Using cdn with lightsail not is validating certificate

Hi people!
I'm trying use the cdn lightsail with my instance wordpress too lightsail, however I'm not can validate the my domain.
My dns zone is at vercel.com, and my subdomain wordpress is wp.mydomain.com. So I pointing wp.mydomain.com to my address ip static lightsail instance.

I need use cdn on my wordpress, however, when I going validate certificate, appears only as Validation in progress…

What's happening ?