Nessus activation code fact is not working

[Vincent--]

This is the output of the command that checks the code currently in use:

# sudo /opt/nessus/sbin/nessuscli fetch --code-in-use 2>/dev/null
Checking...
Could not validate this preference file.  Have installation files been copied from another system?
Failed to fetch activation code

And this is the content of the ::nessus_activation_code variable for the corresponding fact:

# sudo facter -p | grep nessus_activation_code
nessus_activation_code => Checking...

[Vincent--]

After enabling the code manually, the fact is still not working

# sudo /opt/nessus/sbin/nessuscli fetch --code-in-use 2>/dev/null
Checking...
This scanner is using the following Activation Code: XXXX-XXXX-XXXX-XXXX-XXXX

And from facter:

# sudo facter -p | grep nessus_activation_code
nessus_activation_code => Checking...