Sometimes we are not able to fully initialize (set name servers, contacts, auth code) a new domain. In those cases, the grace hours will be zero until we can initialize it.
This does not happen very often. Usually it is because we lose a central registry connection in the middle of processing your order.
Just email us the domain and we can try to initialize it again. Also, about once a day we will check for uninitialized domains and fix them all.