This method gives the possibility to push new vouchers to an existing campaign. New vouchers will inherit properties from the campaign profile. However, it is possible to overwrite some of them in the request body: metadata, additional_info, redemption.quantity, category, code_config. If you provide an optional code_config parameter with a voucher code configuration, then it will be used to generate new voucher codes. Otherwise, the voucher code configuration from the campaign will be used.