UDP mod does not work properly

[Civ01]

Describe the bug
As title says

To Reproduce
Steps to reproduce the behavior:

1. Run SSserver with tcp_and_udp mode
2. Confirm it works on Shadowsocks-rust
3. Run shadowsocks-go client with -u switch
4. Test UDP connections (bittorrent)
5. They arent going through

Expected behavior
UDP working

Desktop (please complete the following information):
Windows 10
ShadowsocksGo2 latest trunk as of October 2021

Additional context
As stated above - shadowsocks-rust version works just fine with the same SS-server