Got email when host is BACK but not when an alert is trigger

[ZeNavigator]

Hi!

We created a bunch of thresholds on battery voltages and activated the "Dead Hosts Notifications".
We are receiving the "Recovering Host Message" alerts but without first receiving the "Down Host Message".
So, we know when a problem fixed itself but are not aware when a battery runs out out of juice.

Is this a known issue?

Thank you for your help