Over the years, we have helped users troubleshoot using the Polar chest straps with our app. We've come up with this set of steps which work when our general troubleshooting is not resolving the issue.
Here are the advanced troubleshooting steps to follow, please do them in order regardless of what you've already done:
Un-pair the heart rate monitor from the Polar app
Un-pair the heart rate monitor from your phone's Bluetooth settings
Un-pair the heart rate monitor from the Elite HRV app (swipe left on the H10 in the "Devices" screen and hit "delete")
Log out of the app (save your login & PW)
Turn Bluetooth off completely on your phone
Turn your phone off for several minutes before turning it back on
Make sure there are no nearby devices that would connect to your Polar H10 (no exercise equipment, laptops with Bluetooth, etc.)
Turn Bluetooth back on
Pair/save the Polar H10 in Soma NPT only - nowhere else. You must be wearing the device for it to connect.
You won't have to do this every time; it will help reset the app, phone, and heart rate monitor. If this doesn't restore the connection, we also recommend discharging the Polar device.
Please ensure your Polar HRM can connect with the Polar Beat or Polar Flow apps. If it doesn't, you'll need to contact Polar, as the strap may need replacing