Error when trying to suscribe on the video socket in a meeting

We want to get the video frame of each participants, but then we try to suscribe to the video socket we have the following error

Error in Subscribe
System.InvalidOperationException: Video 3: Receive media status is not active, cannot perform subscription on the MSI 202

Code Snippet

                else if (mediaType == Microsoft.Skype.Bots.Media.MediaType.Video)
                {
                    logger.LogInformation($"Subscribing to media stream Video.");
                    this.multiViewVideoSocket[(int)socketId].Subscribe(videoResolution, mediaSourceId);
                }

Expected behavior
The expected behaviour is when suscribing, we can retrieve the content of the vidéo socket (the one from webcam).

any ideas ?

Start from the video branch that calls multiViewVideoSocket[(int)socketId].Subscribe(videoResolution, mediaSourceId) and inspect the receive-media state reported in the exception. Reproduce the meeting subscription, then trace why the webcam stream is not active before Subscribe; done when webcam video frames can be retrieved without the InvalidOperationException.