Why fixtime always shown "1970-01-01 07:00:00.000"

I use OSMAnd

I update position using the following:

http://uat.mydomain.com:5055/?id=W1NAN&lat=0&lon=0&timestamp=2018-11-22T08:15:30.000&hdop=0&altitude=0&speed=99&driverUniqueId=W001

Why fixtime always shown "1970-01-01 07:00:00.000"

unixTime

problem resolved.. this is because I did not pass the location data :(
but in some cases, I would not send location data, how to set fixtime to ignore location data and just follow the timestamp?

If location is not provided, Traccar takes last known one.

noted with thanks