When updating the customer, the address data cannot be changed in the same call. To change address data, use put for the endpoint customer/{ident}/addresses/{addressId} and update individually. Only language, customerType, preferredDocumentDelivery and properties can be changed. The debtorAccountNumber cannot be changed. When properties are provided in the update, all existing properties not present in the update will be removed! Matching (by name) properties will be updated, new ones will be added The body needs to contain all the customer addresses for the update to work. Please see Customer Model below for more information regarding required values and input type.