To check if a GPS device is added to a technician's profile, please go to Settings > Staff, click the staff/technician's name, and under the GPS tracker field, you will be able to view if it's added or not.
If the GPS tracker field shows blank, it means that no GPS device is added to the technician.
To add or change the device assigned to the technician, please click the dropdown box and select from the list of available GPS devices.