The bonus is only given for your first item sold. If you placed your listing before January 6th and the product has already been sold, you will receive a €10 bonus. If your first item was uploaded after January 6th, you will receive a €5 bonus.
You can withdraw the bonus in the "Bonus" section of your account. Next to your visible bonus, you need to click "Transfer to wallet" and the money will be automatically transferred to your Eneba account. You can also access it faster via here.
If you do not see the bonus information, press on "GET YOUR LINK!".