Can you please raise a support case for this issue
https://support.precisely.com/contact/
Please save the input data that is being presented to the Modify fields node as a .brd file and attach the .brd file to the case.
You could cut down the fields and records in the sample data to provide the minimum required to exhibit the issue, while maintaining data privacy.
Many thanks in advance
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Adrian Williams
*Precisely Software Inc.
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