My LeakSmart Hub has lost connection to its sensors.

Confirm that the hub is still powered and functioning. Go to the location of the sensor (hopefully the user has already named the sensor(s)).
Power cycle the suspected sensor by removing and reinserting the batteries. Watch to see if the batteries are dead, or the LED pattern on the sensor. Fast blinking means that the sensor(s) are no longer paired, 5 slow links means that the sensor just reconnected to the hub.
Check to see if the sensor is still reported as lost connection. If connection is reestablished, we recommend confirming by simulating a leak on the sensor in question.