First make sure your Bluetooth function in in your mobile phone have been tumed on then remove all the paired Bluetooth device in you cell phone. Then tum off your moblie phone, restart mobile phone and pair with Bluetooth speaker-mic and set the headset read as "default/trust/test/pemit automatically connection/always visible/allow to be found" device, and further ensure that the phone prompt tone is not vibrating mode (because the vibrating impulse wave would interfere with Bluetooth frequency signal sometimes). then repair and connect with your mobile phone. For android system please make sure in the Bluetooth device option list,you have "Phone" options selevted.