Do you get the error: "The tickets are not present on the server or the payment has not been done" ? Then you have already sent the tickets by the Sold Ticket Overview. As the component triggers an invoicing system you can not send them again from this screen.
Below is a screenshot of the erorr:
Please go inside the ticket details by clicking on the order code below:
In this screen you may resend the tickets in the left box.
Note: In the previous screen you are able to recreate the tickets. But not sending them due to duplicated invoices.