Check battery status: Ensure that the AAA battery is properly inserted and oriented correctly in the nano pen.

- Check tip attachment: Please ensure the tip is securely attached.
- Check tip removal: Verify if the device operates with the tip removed.
- Issue when attaching tip: If the device doesn't work when the tip is attached, check for any foreign objects on the tip or adjust the tightness slightly.
- Check tip usage: Confirm whether the tip is new or has been used before.

- If the above Q&A does not resolve the issue, we will process an immediate return or exchange.