Additional bandwidth for a hosting account can be ordered from withing the billing area. You will first need to login to the billing area here
http://www.QualityHostOnline.com/clients
and then go to the menu item as shown below. Place an order for the bandwidth here. This bandwidth shall be available for your account, once your order has been approved. The bandwidth will be billed every month and will not stop automatically, unless requested. Please file a sales support ticket if you do not need the bandwidth any more.