windows 2012 time issue

Hello Team, We have proxmox version 4.4-13/7 . All the windows 2012 vm's getting time change frequently . In event logs we found below event ID 1 The system time has changed to ‎2017‎-‎12‎-‎22T01:42:55.500000000Z from ‎2017‎-‎12‎-‎22T07:12:55.586090700Z. Change Reason: System time synchronized...