why can't see enhanced data by delta loading

Hi Pros,

      I have done enhancement in 0CA_TS_IS_1, which constantly retrieve information and append them into data package, then I tested it in RSA3, successfully. also I load data from this 0CA_TS_IS_1 by full loading, it successes. but when I load data using existing delta load infopackage, there is no expected data loaded. ( ie. there is no enhanced data appended).