Customer has two Lync subscriptions (Subscription 1 and 2 for example). If there are no free phone numbers in both Lync subscriptions button CCP > Lync > Call Groups > Add New Call Group is not accessible, which is correct behavior.
However, if customer has free phone number in subscription 1 the button becomes available in subscription 2 as well. But if pressed - throws message 'No available phone numbers'.
This is due to APSA-6892.
Please contact your account manager regarding the status of APSA-6892