SSIS package runs successfully when i start my SQL server Agent job manually but it went to failure on scheduled time

That time it throws an error message as below:

Message

Executed as user: DOMAIN1\administrator. ...50.1600.1 for 32-bit  Copyright (C) Microsoft Corporation 2010. 
All rights reserved.    Started:  1:00:01 AM  Error: 2015-05-28 01:40:00.82     Code: 0xC0202009     
Source: DFT RequestFactStg OLE DB Command [3499]     Description: SSIS Error Code DTS_E_OLEDBERROR.  
An OLE DB error has occurred. Error code: 0x80040E14.  An OLE DB record is available.  Source: 
"Microsoft SQL Server Native Client 10.0"  Hresult: 0x80040E14  Description: "Uncommittable transaction is detected
at the end of the batch. The transaction is rolled back.".  An OLE DB record is available.  Source:
"Microsoft SQL Server Native Client 10.0"  Hresult: 0x80040E14  Description: "The current transaction cannot 
be committed and cannot support operations that write to the log file. Roll back the transaction.".  End Error  
Error: 2015-05-28 01:40:00.82     Code: 0xC0202009     Source: DFT RequestFactStg OLE DB Destination [3509]   
Description: SSIS Error Code DTS_E_OLEDBERROR.  An OLE DB error has occurred. Error code: 0x80004005.  An OLE 
DB record is available.  Source: "Microsoft SQL Server Native Client 10.0"  Hresult: 0x80004005  Description: 
"The INSERT statement conflicted with the FOREIGN KEY constraint "FK_DateDimStg_TO_RequestFactStg". The 
conflict occurred in database "ENIStageUAT", table "dbo.DateDimStg", column 'DateKey'.".  End Error  Error: 
2015-05-28 01:40:00.87     Code: 0xC0209029     Source: DFT RequestFactStg OLE DB Destination [3509]     
Description: SSIS Error Code DTS_E_INDUCEDTRANSFORMFAILUREONERROR.  The "input "OLE DB Destination Input" 
(3522)" failed because error code 0xC020907B occurred, and the error row disposition on "input "OLE DB 
Destination Input" (3522)" specifies failure on error. An error occurred on the specified object of the 
specified component.  There may be error messages posted before this with more information about the failure.
End Error  Error: 2015-05-28 01:40:00.87     Code: 0xC0209029     Source: DFT RequestFactStg OLE DB Command 
[3499]     Description: SSIS Error Code DTS_E_INDUCEDTRANSFORMFAILUREONERROR.  The "input "OLE DB Command 
Input" (3504)" failed because error code 0xC020906E occurred, and the error row disposition on "input "OLE 
DB Command Input" (3504)" specifies failure on error. An error occurred on the specified object of the 
specified component.  There may be error messages posted before this with more information about the 
failure.  End Error  Error: 2015-05-28 01:40:00.91     Code: 0xC0047022     Source: DFT RequestFactStg SSIS.
Pipeline     Description: SSIS Error Code DTS_E_PROCESSINPUTFAILED.  The ProcessInput method on component 
"OLE DB Destination" (3509) failed with error code 0xC0209029 while processing input "OLE DB Destination 
Input" (3522). The identified component returned an error from the ProcessInput method. The error is specific
to the component, but the error is fatal and will cause the Data Flow task to stop running.  There 
may be error messages posted before this with more information about the failure.  End Error  Error: 
2015-05-28 01:40:00.93     Code: 0xC0047022     Source: DFT RequestFactStg SSIS.Pipeline     Description: 
SSIS Error Code DTS_E_PROCESSINPUTFAILED.  The ProcessInput method on component "OLE DB Command" (3499) 
failed with error code 0xC0209029 while processing input "OLE DB Command Input" (3504). The identified 
component returned an error from the ProcessInput method. The error is specific to the component, but the
error is fatal and will cause the Data Flow task to stop running.  There may be error messages posted
before this with more information about the failure.  End Error  Error: 2015-05-28 01:40:01.86     Code: 
0xC02020C4     Source: DFT RequestFactStg OLE DB Source [1617]     Description: The attempt to add a row
to the Data Flow task buffer failed with error code 0xC0047020.  End Error  Error: 2015-05-28 01:40:01.90
Code: 0xC0047038     Source: DFT Reque...  The package execution fa...  The step failed.

So any pls help me on this...

Most often issue with users. In editing the step in job, you must select proxy user in Run as field.

Create proxy user with sufficient rights to run the SSIS package (for example with sysadmin rights)

EDIT: tutorial for creating agent proxy

EDIT 2: Well, my bad. Didn't see the conflict error in that chaos. Maybe you are just trying to insert bad data now.