When entering the PUK code from the email, please make sure you copy and paste it without accidentally adding any extra symbols.
If you are certain you are entering the exact code from the email and it still doesn't get accepted by the app, you can try resetting your device to factory defaults. The PUK code will also be reset.
To do a factory reset, please follow the steps below.
1. Turn off the band (a message BYE BYE will appear).
2. Press the side button and hold it for about 10 seconds until the sign ERASE appears.
3. Quickly press the button twice. If reset is successful, you will see a message on the screen FACTORY RESET.
After this, all data will be erased from the band and PIN code will be reset to the factory code 000000.
You will need to sync the device with the phone. During this process, new functional firmware will be installed on your device.