How do I unblock the UDP port on my IPhone6splus

with the last update now my application will not work I am on the 14.6 version and one of my apps states Disconnected Network configuration is incompatible with DVRNS connection. NAT type of mobile deice is set as UDP Blocked Please fllow next step for network set up Reconfigure remote network Wi-Fi connection is recommended. This app worked before this last update. It works with wif-fi and hotspot but not data.