Date field changes automatically

I have a date field in my document. When I edit the already published document and add new date field then previous date field changes to the previous date.

Any idea why this is happening?

I have show.timezones setup for the CMS login.


I am not able to reproduce this. Can you reproduce this in an archetype project?

yes, i am facing this in archetype project . if i select Timezone as GMT , then date is being modified automatically.

timezone can be changed to GMT from here .