Add the Ubuntu 20.04 (Focal) image to my box list

After using the command >vagrant box add ubuntu/focal64
I got this error message:

The box ‘ubuntu/focal64’ could not be found or
could not be accessed in the remote catalog. If this is a private
box on HashiCorp’s Vagrant Cloud, please verify you’re logged in via
vagrant login. Also, please double-check the name. The expanded
URL and error message are shown below:

URL: [“https://vagrantcloud.com/ubuntu/focal64”]
Error: schannel: next InitializeSecurityContext failed: Unknown error (0x80092012) - La fonction de rÚvocation nÆa pas pu vÚrifier la rÚvocation du certificat.