To resolve the issue of messages not being sent to a friend in Blockman GO, you can follow these steps:

1. Check Server Status: Make sure that Blockman GO servers are operational. Sometimes messaging issues can occur due to server downtime. You can check for any announcements on their official social media pages or community forums.

2. Verify Internet Connection: A stable internet connection is crucial for sending messages. Check your Wi-Fi or mobile data connection to ensure it is active and stable. If you are using Wi-Fi, try switching to mobile data or vice versa.

3. Update the App: Ensure that you have the latest version of Blockman GO installed. Updates often fix bugs and improve functionality. Go to the Google Play Store, search for Blockman GO, and see if an update is available.

4. Check Chat Settings: Navigate to the settings within the app and check if there are any restrictions on messaging. Make sure you haven’t accidentally turned off chat permissions or blocked the friend you are trying to message.

5. Reboot the App: Close the app completely and reopen it. This can resolve temporary glitches that may be affecting messaging.

6. Clear Cache: Go to your device’s settings, find the app settings for Blockman GO, and clear the cache. This might remove any temporary files that could be causing issues.

7. Re-add the Friend: If the messaging issue persists, try removing and then re-adding the friend in Blockman GO. This can often resolve connection issues between users.

8. Reinstall the App: If none of the above steps have resolved the issue, consider uninstalling and then reinstalling Blockman GO. This can fix deeper issues with the app, although you might lose some saved game data.

9. Contact Support: If the problem remains unresolved, you might want to reach out to Blockman GO support for feedback. They can provide specific assistance for your account.

For a quick visual aid, you can refer to various video walkthroughs available online addressing similar messaging issues, such as those listed on YouTube for Blockman GO - learn more - learn more.

Following these thorough steps should help you to successfully send messages to your friends in Blockman GO. If you need further assistance, feel free to ask!