Hello! I understand that you're experiencing an issue with your V2Box VPN disconnecting automatically after about 15 seconds when configuring it. Let’s work through this together.

1. Check Network Stability: First, can you check if your internet connection is stable? Sometimes, a fluctuating connection can cause the VPN to drop. Try browsing a few websites or running a speed test to see if your internet is consistent.

2. Restart the Application: If your internet seems fine, let's try restarting the V2Box VPN application. This can often resolve minor bugs.

3. Update the VPN: Ensure that you have the latest version of the V2Box VPN. Sometimes, using an outdated version can lead to issues. You can check for updates in the app or download the latest version from the official website.

4. Change VPN Protocol: The VPN might be using a protocol that's causing disconnections. Look for the settings in the application, and try switching between different protocols, like OpenVPN, IKEv2, etc.

5. Firewall/Antivirus Settings: Check if your Mac’s firewall or any installed antivirus software might be interfering with the VPN connection. Try temporarily disabling them to see if that resolves the issue.

6. Log Files: If the problem persists, it can be helpful to check the VPN's log files for any error messages that might indicate the cause of the disconnection.

If you've tried some of these steps already or if you're still facing issues after this, please let me know, and we can explore further options or escalate this issue! Are you satisfied with the solution I provided?