Unable to unlock nodes
In some cases, it may happen that some nodes appear to be locked but when clicking the unlock Node/Tree, an error is returned that the nodes are already unlocked
There might be a corruption in the JCR lock files.
Check if you have any invalid lock entries in the lock files under '/digital-factory-data/repository/workspaces/default/locks' as mentioned in this article. If that does not help, you try to run the undocumented 'JCR Lock Check Tool' which can found at http://JAHIA_URL/modules/tools/checklocks.jsp. First, run the tool with the option 'Run Java Content Repository integrity check' and if it returns invalid locks, you may try to run the fix option.
As mentioned in the tool's page, due to the low-level JCR operation performed by this tool, you must run it in the full read-only mode, shut down all other cluster nodes before running it. Also, Jahia must be restarted after applying the fix. Finally, please make sure to have a proper backup as well in case anything went wrong.