On most DVRs & NVRs, you can go to Settings > General > Date & Time to adjust the date / time settings after to login as you normally would.
System Time
Here is were you can set the correct date and time.
Time Zone
The correct time zone for Eastern Time is GMT -5
Daylight Savings Time
If you'd like the DVR to automatically adjust for Daylight Savings Time, make sure there's a check mark next to DST and select the dates and times when Daylight Savings time should begin and end. Click here to see when Daylight Savings Time begins and ends.
Automatic Time Adjustment
If you'd like the DVR / NVR to automatically sync to the correct time, make sure there's a check mark next to NTP. Your DVR must be connected to the internet for time sync to work.
Once you're done making changes, be sure to click Save or your settings wont take effect.