Most heart rate monitor problems are caused by the strap. Dirt, sweat and other impurities often build up on it, causing connection problems.
We recommended rinsing the strap with warm water after every use, and machine washing the strap inside a laundry pouch after every fifth use. Most straps can withstand approximately 100 washes at 40ºC/100ºF with common laundry detergents.

If you have any problems connecting your Smart device, please check: 
- that the monitor is not connecting to any other app 
- remove the monitor from your phone's Bluetooth settings and  connect it directly from the app settings 
- while pairing on some devices you may need to turn on location service and turn Wifi off
- Even if you don't get the device connected you can check if it still works during a workout. Start a workout and check if it is still connected.