External Heart rate monitor

I am having to replace the battery in the Polar H10 every 2 months or so with only 6-8 hrs a week of sport activities.  

I think it is continuously running in the background when not worn.  If the monitor is off and hanging in the garage and I looking at Sensor & Accessories I see that it is connected.  
If I try to do a health snapshot with the hrm in the garage it picks it up and gives a 0 heart rate. 

I have started to disconnecting it after each use.  

Anyone else hav ethos issue?