We have identified an issue with the current versions of the Greenbone Free where not enough disk space is available to process feed updates. This is due to improvements to the feed recently which increased the feed size.
We are preparing a new version of the Greenbone Free to fix the issue, however I do not have an ETA yet.
As a workaround, you can download the Greenbone Free again and after starting it disable the feed update as per 7 Managing the Greenbone Operating System - Greenbone Enterprise Appliance – GOS 22.04.27.