# External voucher codes *This function is not yet available to all of our users. If you wish to use it, please **contact us**.* If the voucher comes from an external source, the code on the ticket will come from a list of pre fixed codes. The codes from the lists come in order, and will be put on the tickets one after another, in the order of purcahse. So in this case, it is not our system that generates the codes to the tickets. This method enables you to use external numbers and code ranges from a system other than ours - and thus system the codes came from will accept them as valid. The code ranges must be uploaded to the tickets in csv format, and each code has to be unique. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.cooltix.com/cooltix-support/organizers/order-settings/external-voucher-codes.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.