There is an in-game currency Black Gems (BG) used on servers.
When in the game click on the Black Gems image on the resource panel or on the number of BlackGem amount.
Choose
the payment method in the displayed dialog box:
The account activities and its state can be ckecked by clicking "Financial account" in the server selection screen
You can transfer the Black Gems from any server (where you have continuous subscription) to another one. For this purpose use the "Portal Purse": transfer BG to Portal Purse first, and from there to the server you`d like.
You can always add BG from the Portal to any server or withdraw them from respective server (if you have active Subscription).
Common payment mistakes