Roon Arc suddenly stopped working

I’m away in week 3 (-;)) of my holidays. Up to yesterday, Arc worked seamlessly but yesterday it stopped working. No change whatsoever on my side on server or ruter settings.
I can’t access my server remotely, but I can access my router (unifi Dream Machine).
The error I”m getting is a port forwarding issue.
Meanwhile, Plex & Plexamp keep on working perfectly & remotely on the sane server.
Also the server (mac mini m1) is programmed to restart everyday, but that doesn’t solve the issue

Any suggestion on how to solve this remotely with the limitations stated above? Or should I patiently wait to return home to access my server?

I’ve tried the following so far: 1) restart router, 2) turn on/off dlna on router, 4) turn on/off antivirus and firewall on router, 5)restart server.
None has worked

Hi @Ricardo_Damborenea,

According to diagnostic logging, another software program on your Mac server has taken over the port you’d manually configured for RoonServer/ARC.

ARC’s attempts to reach the RoonServer machine are timing out.

With automatic configuration, RoonServer tries a different port on each startup if the router reports that the port is occupied. However, manual configuration of port forwarding prevents RoonServer from parsing additional ports. Unfortunately, you’ll need to update the port forwarding rule in both RoonServer and your router web administration settings to remedy this situation, requiring access to your local network.

Thanks @connor

Could it be Plex that has taken over the port?
Anyways I understand from your answer that I will only be able to fix the issue when I come back home