It sounds to me like you are using client specific transport route
from VIR to your production system and there is at least one
transport sitting in the import queue of VIR without a client
assigned to it. Scroll through the import queue and you will see
a red box where a client should exist. This means it still needs
to be assigned a client. As VIR is virtual simply assign it to the
client that makes the delivery route.
At first glance you should also be able to tell if a transport
exists without a client as there will be a new button at the top
of the import queue that says, "Set Target Client"