Updates the details of an existing beneficiary. Only profile fields (name, address, city, postal code, country and visibility) can be edited. Bank account details captured at creation (currency/asset type, bank country, IBAN, account numbers, sort/routing codes, BIC/SWIFT and the Currencycloud-specific identifiers) are immutable: they are marked read-only and any value supplied for them is ignored, the stored value is preserved. To change bank details, delete the beneficiary and create a new one.