Ubuntu – Issue Updating Plugins on Nessus 10.8.3

I have installed Nessus 10.8.3 on a Kali Linux VM, but I’m encountering issues when trying to download plugins.

Here’s the error message from the Nessus UI (browser):

Nessus
Download Failed
An unexpected error occurred while downloading plugins. This could be due to a network error, lack of disk space, or something else entirely. Please take one of the following corrective actions:

When I attempted a manual update using the command:

sudo /opt/nessus/sbin/nessuscli update –plugins-only

I received the following output:

Refreshing Nessus license information… complete; continuing with updates.

—– Fetching the newest updates from nessus.org —–

[error] Nessus Plugins: Did not get a 200 OK response from the server: HTTP/1.1 503 Service Unavailable
Nessus Plugins: Failed

Failed to update Nessus Plugins **

I’ve confirmed my network connectivity and ensured there’s enough disk space available.

Could you please assist me in resolving this issue?

Thank you.

Installation on Ubuntu and on my host.
sudo /opt/nessus/sbin/nessuscli update –plugins-only