Socket error on iOS apple review team

Apple review team cannot connect to our dedicated server. Logs are attached and as following:

[2020.10.22-19.26.12:125][729]LogSockets: Warning: Unhandled socket error! Error Code: 316. Returning SE_EINVAL!
[2020.10.22-19.26.12:125][729]LogSockets: Warning: Could not serialize ///, got error code SE_EINVAL [5]
[2020.10.22-19.26.12:218][729]LogNet: Game client on port 7782, rate 10000
[2020.10.22-19.26.13:232][791]LogHandshake: Verbose: Initial handshake packet timeout - resending.

So how can I debug more or get information to fix this SE_EINVAL error. Also what is the error of not being able to serialize adress of server?