During data ingestion, you get the above error message despite the field not being required. What is the definition of ‘required’ in this case?
For a field marked as ‘Required’ in the XDM schema, this means the field has to be present in the incoming data for validation purposes.
If ‘Not required’ but present then it must adhere to its definition, ie: with ‘string’ value as opposed to no value at all.
null is not accepted/supported by AEP ingestion process. If a field does not have a value, then it must be excluded from the payload.