Hi @TAKAO.KANAZAWA,

This topic needs to be investigated. Could you please send us a ticket by using our Contact Form from the Help Center (bottom left corner) https://help.trackunit.com/en/ or by sending a request to support@trackunit.com

Please provide us all the details like : unit serial number, date and time.

Thanks in advance.

Wishing you a nice day

BR 

Loris