R03B551 did not return batch number

follow doc id 1458481.1 to implement automatic Cash receipts.  Create a custom UBE to

1) read csv file and insert data into F03B13Z1

2) call UBE R03B551.  This UBE also generate the batch number and insert into Z table

3) using the data structure of R03B551, return the batch number data item

4) using the batch number and call UBE R09801 to post

With surprise, the UBE R03B551,  generate a batch number and insert into Z table, it did not return the batch number even the batch number is part of the Data structure in this UBE Interconnections.

I though if the batch number is in the data structure of UBE Interconnections, the batch number should be returned.