info your posts is insufficient to replicate the issue so any response is going to be a wild guess.
are you sure the IP address is correct? what was the configuration like, when you used TCP protocol?
if TCP was working, what was the reason to change to UDP? configuration shows that external node is a client. that means robot is acting as a server. client can only make connection if server is actually running.
is it running? in what interpreter? why is there 10ms ping for alive signal? IPO time is 12ms so every PING will fail. this means that if you are using ALIVE in your program to check for lost connection, it will keep closing any connection automatically. did you add means to monitor how many times this happens (add counter for example).