How to Update the room property after the room created?

I want to Clinet send a request to server,then the Server decide who get which card. and then server Update the room property.

var setPropertiesOperation = new SetPropertiesRequest(peer.Protocol, operationRequest);
setPropertiesOperation.Properties.Add("cards",p.Cards);
setPropertiesOperation.OnStart();
this.HandleSetPropertiesOperation(peer, setPropertiesOperation, sendParameters);
setPropertiesOperation.OnComplete();

I used "SetProperties" ,it doesn't work. Client can't get Properties. Where is my mistake