date and time not update in table

Hi All!

In an userexit i am writing the code as below :

likp-zzdnstatdate = sy-datum.

likp-zzdnstattime = sy-uzeit.

I am assigning the date and time to likp for a particular document.But the fields are not getting updated they are shomwing the old values.Interestingly in debugging mode i could see the change.Since I can't use commit in user exit how to solve this..

Please advise

Regards

Praneeth