You have a StorNext volume.
When new folders and subfolders are created on the directly attached StorNext volume, finder enumerations exhibit various behaviors.
Since no change journal or notifications will work against StorNext and the default time for the entry expiration is 5 minutes, this can cause stale enumeration issues.
The best practice to set the registry key EntryExpirationTime to 5, 10, 15 seconds.
Contact Acronis Files Connect support if you need assistance.