Sherpa Single Top Generation TRUTH0 and TRUTH1 Problem

Hello, i have generated the TRUTH0 and TRUTH1 root file for the tW generation. However, from the ntuples of TRUTH0, the information of parton level are empty. Also, from the ntuples of TRUTH1, the boson level are empty. Here are the TRUTH0 and TRUTH1 directories:

TRUTH0 : /afs/cern.ch/work/k/ktam/public/QT/tW_channel/TRUTH0_50000

TRUTH1 : /afs/cern.ch/work/k/ktam/public/QT/tW_channel/TRUTH1_50000

After using the validation tools, the information are empty.

Thank you

Terry