Have you checked the time zone of your browser and the time zone of your ERPNext server.
Be aware that the database recording time, the server’s displayed time and the client device displayed time can all be different, yet still all be correct.
You will also find that each user in ERPNext has the option to specify their own time zone setting, and the ERPNext server’s time zone can be set in System Settings.
What operating system do you have client-side and server-side?
More info: [Solved] Where does ERPNext get it's System Time and Date?
@felix linked to a dead page in his post. The new link ought to be:
(I would have corrected the link in that thread, but it’s locked, of course. We all understand the enormous importance of locking threads in this forum.)