Hi karin,
at ECC Side Tx - RSA2, check the delta method for this data source.
Seems like while creating time, they created as generic rather than time stamp based.
http://scn.sap.com/thread/1252434
Two possible ways:
1. Need to delete existing data source and create new one with the same name time stamp based data source (be careful.)
Or
2. Raise to SAP, take SAP Assistance.
Thanks