Your second number has call and SMS limits that are renewed monthly as part of the Premium subscription. Your call limits are determined as minutes and SMS limits are determined as units. You can view your limits by clicking info button at the section with your number on home page. These limits are only valid for outgoing calls. Incoming calls and SMS are subject to a monthly fair usage policy.
Call limits may vary by region. The benefits provided in your subscription package are renewed monthly with your Premium subscription, and any unused benefits do not transfer to the next month.