Unidentified driving time is a special type of duty status entry. These statuses are held in the tablet memory from when a vehicle is moved without a driver logged in.
These duty status entries can be claimed, or added to a driver's daily log from the login or logout flows by pressing the large orange banner.
Please note that adding duty statuses that aren't your own may result in log entries that impact your hours of service and may render you without hours to drive.