Why did I fail to set up my Onvis Smart Multi-switch HS2 to Onvis Home app?

(1) Make sure Bluetooth is enabled in your iOS device. 
(2) Make sure your HS2 is within connecting range of your iOS device.
(3) Before set up, reset the device by long pressing the button in the center for about 15 seconds until LED blinks red, green and blue once. 
(4)  Scan the setup code on the device, instruction manual or inner packaging.
(5)  If the app prompts “couldn’t add the device” after scanning the setup code:
      a. remove this HS2 that was added before and close the app;
      b. restore the accessory to factory settings;
      c. add the accessory again;
      d. update the device firmware to the latest version.