Manage old data - no old data found

Hi,
we have upgraded our Jenkins version to the latest stable one. Jenkins is running inside a docker container and jenkins_home is a volume on the host system.

In “Manage Jenkins” we see an indicator at “Manage old data” with a number of over 4000 but “Manage old data” displays a message “No old data found”.

Any ideas why nothing is displayed? Is it too much data that Jenkins cannot display it?

Thanks.

Running this in the script console should delete the old data

import hudson.diagnosis.OldDataMonitor 
odm = OldDataMonitor.get()

odm.doDiscard(null, null)