Now that I think about it, it's happening since I've downloaded the dedicated server from steam yesterday morning. Could that have broken the multiplayer?
The single player works as always.
P.S I've found this in my rgl_log, hope it helps:
[12:06:00.021] Http Post Request with message failed. Exception status: SendFailure
[12:06:00.023] Exception 0: The underlying connection was closed: An unexpected error occurred on a send. ||| StackTrace: System.IO.IOException: Authentication failed because the remote party has closed the transport stream.
at System.Net.TlsStream.EndWrite(IAsyncResult asyncResult)
at System.Net.ConnectStream.WriteHeadersCallback(IAsyncResult ar)
[12:06:00.023] Exception 1: Authentication failed because the remote party has closed the transport stream. ||| StackTrace:
[12:06:00.023] ClientRestSessionTask::SetFinishedAsFailed::TaleWorlds.Diamond.Rest.ConnectMessage
[12:06:00.023] ClientRestSessionTask::SetFinishedAsFailed:: TaleWorlds.Diamond.Rest.ConnectMessage done
[12:06:00.036] [][] New MBGameClient State: Idle old state:Working