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So far, custom field data was available (where filled) including in the section 'GENERIC_VALUES' in the get request as a map of key-value pairs with the key being the field name (applicable to company and traveller profiles).
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Starting from November 1st, 2022 we will only support the new section GENERIC_FIELD_VALUES for getting custom field data (where filled).
This new section includes besides of the field name and the value also the UUID number of the custom field.
Updates to a custom field can be done using the field name or uuid, where uuid however has priority over the field name.
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