Alarm Phone Notification with Grandstream HT813 doesn't work anymore after windwos 11 update

The Alarm Phone Notification configured with a Grandstream HT813 doesn't work anymore, probably due to a Widnwos 11 update.
The server and the VoIP gateway are under the same subnet and the firewall on the server is down.
When testing a phone pipeline the log display errors like "Network is unreacheable: Datagram send failed", "input/output error" and as you can see in the screenshot of the log.

I saw this response by @pturmel Ignition VOIP Voice Notificaiton Profile- Not Registering - #2 by pturmel that hints that the problem is in the net and in the OS.
I'm not a good network technician, is there anything I should try on the server or suggest to my client network technitian to try?
Thank you


after some suggestion from my local distributor and some tests the alarm calls work again (for now)
I have specified the Local Bind Address because the server has two network cards, but when saving this error appeared

After editing again (chnaging nothing) and saving the error disappered but, testing a pipeline, the alarm calls still didn't work but the Agent errors didn't appeare in the log.
So, just for testing I tried removing the Local Bind Address, saved, and when testing the pipeline now the alarm calls works.
Any idea how this happened? What's the cause?
(I'm sure this is going to fail again in a week if I don't understand the underlying problem.)

Did this ever fail again or did you figure out the issue?