Hi Ted,
I've assumed straight away that you're missing key fields. Also, I would use REFWO rather than WONUM (one's persistent). It would normally check the primary columns using Database Configuration, but that is not telling the correct story in this can. Have a look at the below index and see if adding these feilds resolve your issue.

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Craig Kokay
Principal Consultant
COSOL
email:
craig.kokay@cosol.global#IBMChampion
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