Hi everyone! My team has been working with the Application that provides proxy service for other devices in the same subnet. We use PacketTunnelProvider to setup a TUN interface binding with certain IP addresses, then bind listen sockets to those IPs. so that any device in the same subnet(such as WiFi) that set phone as gateway, whose traffic to those IPs will be capture by listen sockets we bound. This approach works fine in previews iOS version and Android OS. The problem is, after new system update 13.6 arrived, we received tons of feedbacks from our users that the proxy is not working. We looked into it just to find the listen sockets cannot receive packets from subnet anymore. The problem remains the same in iOS14. We have tried binding the socket to 'en0' by setsockopt, which is the WiFi interface; binding the socket to 0.0.0.0. but still have not luck. Now my team is at a complete loss. The business is temporary down for new iOS system user. Any suggestions would be greatly appreciated, and I'd be happy to provide more information.