command line:
sudo date -s "Thur Apr 4 12:00:00 UTC 2019"
also can check date to see if your timezone is correct, etc. sudo raspi-config (in localization options) to change your timezone
I think there were some issues with not being able to use a network time server Ah - the CM3 does not have a real time clock (RTC) to keep the time set when the unit is not-powered so I think it gets reset by the network when it boots?.