Custom domain error after transfering a pages project to another account

As Cloudflare pages doens’t allow to transfer a project to a 3rd party account, I have follow the steps in this topic: Transferring Cloudflare Pages projects to another account - Developers / Cloudflare Pages - Cloudflare Community

As I first deleted the project in the old account, I could create the project in the new account with the same name, ie, it has the same *.dev domain.

The problem is that after I created the subdomain in the project in the new account, it doesn’t get validated. And when I enter to the custom domain I’m getting ERR_SSL_VERSION_OR_CIPHER_MISMATCH error.

As the CNAME record should have the same value (the new project has the same name as the old one), I didn’t change anything in the DNS management service (I’m not using Cloudflare to manage this domain). What should I do in order to fix this?.