If you’re experiencing issues with IPv6 traffic over VPN, you can disable IPv6 for a specific connection in Ubuntu (or other Linux distros using NetworkManager). This ensures the change applies only to that connection, without affecting others.

1. List all NetworkManager connections

Run the following command:

Look for the profile name that corresponds to WiFi (e.g., MyWiFi).
 

2. Disable IPv6 for that specific connection

Replace  with the actual profile name from the list:

3. Restart the connection to apply changes

This deactivates and reactivates the connection so the new setting takes effect immediately.

4. Verify IPv6 is off

Run the command below:

Expected output:

This confirms IPv6 has been disabled for the selected connection.