Hello @Valentine1
As long as you do not receive a confirmation by mail, the purchase is not completed and the payment is only pending. With Twint, the payment is only pending and then reversed by Twint within 10 days. With Twint there are sometimes interruptions in the payment process, so that the transaction is not completed by Datatrans. I recommend you to try the purchase again and otherwise use another payment method.
Kind regards, VlaznimA.