You created an Extension Field either via PDI or Adaptation Mode and maintained the respective data type in Code List Mapping. However, the mapping is not working for this extension field.
Only standard fields are supported in Code List Mapping. The mapping will not work for extension fields although the respective Data Type of the extension field can be maintained in Code List Mapping,
As workaround, you can implement a custom logic to translate the values of the extension field in your middleware.
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