LS Mediation Server error 25027

Hi,

I have an error when I try to make a call through a SIP trunk.

The mediation server encountered an internal exception from the signaling layer. The current call can be deleted. The mediation server will continue to run.


Exception : System.MissingMethodException: Méthode introuvable : 'Microsoft.Rtc.Internal.Collaboration.Media.CodecId Microsoft.Rtc.Internal.Collaboration.Media.H264VideoMediaFormatSet.get_CodecId()'.
   à Microsoft.Rtc.Collaboration.AudioVideo.MediaSessionAgent.ProcessGenerateAnswerWorkitem(GenerateAnswerWorkitemAsyncResult workitem)
   à Microsoft.Rtc.Collaboration.AudioVideo.WorkitemQueue.ProcessItems()
   à Microsoft.Rtc.Collaboration.AudioVideo.SerializationQueue`1.ResumeProcessing()
   à Microsoft.Rtc.Collaboration.AudioVideo.QueueWorkItemState.ExecuteWrappedMethod(WaitCallback method, Object state)
Nom de la méthode : ResumeProcessingCallback

Cause: Internal error.
resolution:
Examine the previous error messages in the event log to determine the potential cause and report it to the support services.

Help please

Sami,