In order to make your payment at Papaki via web-banking, use the Electronic Payment Code, which you find in the ordering email (or in the Control Panel if it is a service renewal / upgrading).
Specifically, the procedure you should follow is:
1. Log in to Piraeus Bank web-banking.
2. In your account's administrative environment, select Payments in the menu that appears to the left and then By category. After selecting the Internet Services category, find and select Papaki from the list as shown below.
3. After selecting the billing account, fill in your name, e-Payment Code and payment amount and click Continue to complete the process.