I have a WordPress site with a 2Gb disk quota. After Cyberpanel detected that the account reached disk quota, it was impossible to update WordPress plugins. The update would fail with message "Update failed: Could not create directory."
We then manually deleted files so that the account shows 58% of disk quota used:
Even though there is now space available in the account. Upgrading WordPress plugins still fails in the same way. Cyberpanel is acting as if the account was still over disk quota.