Hi there! I see you're encountering an "unknown error code 3" when trying to register in Blockman GO on your Android 13 device using the WebKit browser. Let's see if we can get this sorted out together.

First, could you tell me a bit more? For example:
- Are you using any third-party login options (Google, Facebook, etc.) or registering with email?
- Have you tried restarting the app or your device before registering?
- Are you connected to a stable internet connection, Wi-Fi or mobile data?
- Have you attempted registration multiple times, or is this the first try?

Meanwhile, here are some common steps for this type of error which often relates to connection or app cache issues:

1. Clear the App Cache and Data
- Go to your device Settings > Apps > Blockman GO.
- Select Storage & Cache > Clear Cache, then Clear Storage/Data.
- Restart the app and try registering again.

2. Check Network Connection
- Make sure your internet connection is stable. If you’re on Wi-Fi, try switching to mobile data or vice versa.
- Sometimes using a VPN can cause registration errors—if you have one enabled, try disabling it temporarily.

3. Update the App
- Ensure you have the latest version of Blockman GO installed from the official store.
- Outdated versions can sometimes cause unexpected errors like "unknown code 3."

4. Try Reinstalling the App
- Uninstall Blockman GO completely.
- Restart your device.
- Download and install the latest version again.

If these steps don’t resolve the issue, it might be related to server-side problems or account verification glitches. In that case, please let me know, and I can guide you through checking your account or contacting Blockman GO support directly.

Would you like me to walk you through clearing cache and reinstalling the game step-by-step? Also, did you notice any other error messages or unusual behavior before this error appeared?

Looking forward to your reply!