There may or may not be power to the OBD port itself. To verify this follow this list of troubleshooting steps.
Verify that the dongle is securely connected to the port-not loose or improperly positioned
Check for any damage to the port: Loose wires behind it, broken pins, damage to port connector
Check the owners manual for a fuse that powers the port and replace it if it has blown
If possible verify with a scan tool that the port has power: It will not be able to scan the vehicle with the port not having power.
After you have checked all of the above and it is determined the port has power, but the dongle is not working contact Retail Technical Support: 1-877-765-7269