Voucher number is not updating in projJournalTrans table

HI,

 Am importing the data from CSV to ax (projJournalTable and projJournalTrans) using x++ code ,

DAT/Project management and accounting/Area page -->Hour journal

I can able to insert the data successfully ,when i try to post its showing error like,

(A key with the name 0.00 already exists)

This error causes of Voucher number is not updating in  projJournalTrans table

if manually creating  journal are   voucher number is created,

when i try to run using code voucher number is not creating  ,pls give any idea  to solve this issues  .

Regards

Siva Kumar