Your ReadiBand must be preassigned to your user account. You don't have to pair the band with your phone.
To see if it’s preassigned, make sure Bluetooth is enabled on your phone, then sign in to Readi on your Android phone or iPhone. If your band is already assigned to your account, it will connect to your phone automatically within a minute of opening the app.
If it’s not, the app will tell you that no band is assigned to your account and you’ll need to talk to your program manager.