A device can be suspended for a variety of reasons. To resolve the suspension:
In case the suspension is related to a hardware issue first try to deactivate and reactive it.
If the device cannot be activated or remains in a suspended state, reboot the device by unplugging it and plugging it back in. Then take the vehicle on a short trip above 5mph for at least 5 minutes.
If the device remains suspended, verify your billing information is up-to-date.