I know I'm not very active here in the community but I did a little step by step that should help especially those who use DNS CloudFlare.
Edit the LetsEncrypt configuration file:
Insert the line:
Enter your cloudFlare token and email with the parameters below:
Then save the file and restart the services with:
wo stack restart
Now you should be able to issue SSL with:
wo site update dominio.com --le --dns=dns_cf
I also made a short step-by-step video.
Hope Google Translate translated well.