This is most likely to happen after a power outage.
- Go down to the electrical room behind 00.
- Open the upper of the security panels on the North Wall (the wall that is shared with 00).
- Find the Synergis Cloud Link controller in the lower right and disconnect the ethernet cable and the power cable (those are the only two cables).
- Reconnect the ethernet cable and then the power cable.
It might take a minute or two for everything to work again.