> For the complete documentation index, see [llms.txt](https://docs.zaui.com/io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.zaui.com/io/api-function-definitions/booking/update.md).

# Update

The booking amendment request allows you to submit amendments to existing bookings created through your implementation in the supplier system. To request a booking to be changed, your request must submit through a valid booking reference number, and that booking must have been originally created through your implementation. Each booking amendment is for a single booking only.