Using LUX Walker:
LUX Walker requires that you open TCP port 843 for multiplayer networking.
If you are experiencing any other issues you can try open the following ports.
TCP: 4530 4531 4533 9090 9091 9093
UP: 5055 5056 5057 5058
Fore more information see here: https://doc.photonengine.com/en-us/server/v3/reference/tcp-and-udp-port-numbers
If you have any further Questions, please contact firstname.lastname@example.org