Event organisers can cancel ticket orders directly from the admin panel. Cancellation marks the order as cancelled in Eventify. It is separate from a financial refund — see How to Issue a Refund if payment was made via Stripe and you need to return money to the attendee.
Cancelling keeps the order on record. To remove a test, duplicate or wrong order completely, use Delete Order instead. See How to Delete a Ticket or Booth Order on Eventify.
The Cancel option is available when:
Go to Tickets → Sales Report. Make sure you are on the Orders tab.

Find the order using search or filters, then click anywhere on the order row to open the Order Details panel.

In the top action bar of the Order Details panel, click Cancel Order.

A confirmation dialog appears. Review the details and click Cancel Order to proceed.
The order status immediately updates to Cancelled. A success message is shown and the panel closes.

No. Cancelling does not automatically process a refund. Issue a refund separately if payment was made.
No. Cancellation cannot be undone, and any issued tickets or QR codes are no longer valid.
Delete it. Cancelling keeps the order in your reports with the status Cancelled, while deleting removes the order, and any attendee who only existed because of it, from Eventify. See How to Delete a Ticket or Booth Order on Eventify.