Hi,
Two ways you can do this issue:
1. Just delete the wrong record(selective deletion) and do the repair full load if source have the correct data.
2. Other wise you can delete the request from cube and do the correction(if possible) at PSA.
After that you can relaod the same request from PSA to target by using update from scheduler or do reconstruction.
Based on above two possibilities you can follow any one method.
Thanks