diff --git a/Assets/Mirror/Runtime/Transport/LLAPITransport.cs b/Assets/Mirror/Runtime/Transport/LLAPITransport.cs
index 64f8e8794..5b0a3a0ab 100644
--- a/Assets/Mirror/Runtime/Transport/LLAPITransport.cs
+++ b/Assets/Mirror/Runtime/Transport/LLAPITransport.cs
@@ -116,6 +116,8 @@ public override bool ClientSend(int channelId, byte[] data)
 
         public bool ProcessClientMessage()
         {
+            if (clientId == -1) return false;
+
             int connectionId;
             int channel;
             int receivedSize;
@@ -200,6 +202,8 @@ public override bool ServerSend(int connectionId, int channelId, byte[] data)
 
         public bool ProcessServerMessage()
         {
+            if (serverHostId == -1) return false;
+
             int connectionId = -1;
             int channel;
             int receivedSize;