My Polar H10 HRM won't connect to Apple Watch

So, i thought that if I turn off HR sensor on my apple watch via privacy settings I would be able to connect my Polar H10 HRM and be sure that the readings would come only from Polar, but even if it says that it’s connected via bluetooth it doesn’t read anything…does that mean that HR must be always enabled in privacy settings so that the apple watch could even read data from any external HRM’s? Because this way it keeps disconnecting and switches back to it’s own optical sensor…it’s very annoing…

[Re-Titled by Moderator]

Original Title: Apple watch and Polar H10 HRM