a) Make sure your headset and the mobile device are within the 8-10m range to each other. Low battery level may cause the disconnection from the mobile. If the battery level is less than 10% charge the headphone

If this does not solve your issue then:

 b) Set your Mobile Phone to Airplane Mode and then again normal mode. Mobile's BT working will back to normal if any unknown error is happening with BT

c) Chances are, you might have an issue with the mobile. You can check if the headset is working well using a different mobile. 

d) Restart mobile phone to refresh Mobile Phone's working now again try and follow the pairing process

e) RESET the device (Neckband)

f) After following the above process, if the issue still persists with an alternate device please raise a complaint on our support portal.