Why does the router suppress udp?

Question

Android

Good afternoon, there are two android devices connected via wi-fi. They exchange udp packets, but the packets do not reach.
If you run applications on emulators and connect computers with a cable, then everything works fine. If you do the same through wi-fi, then the connection disappears. I tried a bunch of different ports. What setting should be done?

Answer 1

Ports need to be opened.