job cancelled every one hour

Hi,

When i am checking in SM37 cancelled jobs ,SWWERRE job failed every one hour.job log is showing like below.

Job started

Step 001 started (program RSWWERRE, variant &0000000000004, user ID WF-BATCH)

Starting Background Steps in Status "Being Processed"

==> 0 background steps started

==> 0 error(s) occurred (  > see application log)

ABAP/4 processor: CONVT_NO_NUMBER

Job cancelled

Thanks&Regards

Ramakrishna