diff --git a/Consul.Test/SemaphoreTest.cs b/Consul.Test/SemaphoreTest.cs
index 468c599d4fdd..d5f1cf177874 100644
--- a/Consul.Test/SemaphoreTest.cs
+++ b/Consul.Test/SemaphoreTest.cs
@@ -112,6 +112,29 @@ public void Semaphore_AcquireRelease()
             Assert.IsFalse(s.IsHeld);
         }
 
+        [TestMethod]
+        public void Semaphore_AcquireWaitRelease()
+        {
+            const string Name = "XService";
+            const string Prefix = Name + "/lock";
+            const int Limit = 1;
+            var _semaphoreOptions = new SemaphoreOptions(Prefix, Limit) { SessionName = Name + "_Session", SessionTTL = TimeSpan.FromSeconds(10) };
+            var c = ClientTest.MakeClient();
+
+            var s = c.Semaphore(_semaphoreOptions);
+
+            s.Acquire(CancellationToken.None);
+
+            Assert.IsTrue(s.IsHeld);
+            Thread.Sleep(30000);
+            Assert.IsTrue(s.IsHeld);
+
+            Assert.IsTrue(s.IsHeld);
+
+            s.Release();
+
+            Assert.IsFalse(s.IsHeld);
+        }
 
         [TestMethod]
         public void Semaphore_Contend()
diff --git a/Consul/Session.cs b/Consul/Session.cs
index bde05cfffd4a..87d19467d1aa 100644
--- a/Consul/Session.cs
+++ b/Consul/Session.cs
@@ -325,7 +325,7 @@ public Task RenewPeriodic(TimeSpan initialTTL, string id, WriteOptions q, Cancel
                         try
                         {
                             var res = Renew(id, q);
-                            if (res.Response != null)
+                            if (res.Response == null)
                             {
                                 lastException = new TaskCanceledException("Session no longer exists");
                             }