When you receive a gift card payment this shows in your dashboard as a payment with "gift card".
Be careful: It's possible to use another payment method, together with a gift card. This is also known as a stacked payment. In the event of a stacked payment, the additional payment method won't be shown in the dashboard, but only as a total of a gift card payment.
For example, €10 via a gift card and €40 via iDEAL, this will show as €50 paid by gift card in the Dashboard statistics. Only when you click on the details of the gift card payment, you will find the details of the gift card and the other payment (when applicable).