diff --git a/Pilz.Net/Api/ApiServer.cs b/Pilz.Net/Api/ApiServer.cs
index 5557680..e24f0c3 100644
--- a/Pilz.Net/Api/ApiServer.cs
+++ b/Pilz.Net/Api/ApiServer.cs
@@ -100,13 +100,14 @@ public class ApiServer(string apiUrl) : IApiServer
     {
         if (MaxConcurentConnections == int.MaxValue)
             return; // Unlimited in this case
-        semaphore ??= new(MaxConcurentConnections);
+        semaphore ??= new(MaxConcurentConnections, MaxConcurentConnections);
         semaphore.Wait();
     }
 
     protected virtual void FreeSlot()
     {
-        semaphore?.Release();
+        if (semaphore != null && semaphore.CurrentCount < MaxConcurentConnections)
+            semaphore.Release();
     }
 
     public virtual void RegisterHandler<T>(T instance) where T : class