From 28a2a0c7fd451352c282fee16079e0caa2a12d00 Mon Sep 17 00:00:00 2001
From: JKorf <jankorf91@gmail.com>
Date: Tue, 13 Jan 2026 22:11:18 +0100
Subject: [PATCH] Fixed semaphore exception when creating a new REST client
 while time sync is in progress on another client

---
 CryptoExchange.Net/TimeOffsetManager.cs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/CryptoExchange.Net/TimeOffsetManager.cs b/CryptoExchange.Net/TimeOffsetManager.cs
index 12f2746..66b9a00 100644
--- a/CryptoExchange.Net/TimeOffsetManager.cs
+++ b/CryptoExchange.Net/TimeOffsetManager.cs
@@ -113,7 +113,8 @@ namespace CryptoExchange.Net
         /// <param name="api"></param>
         internal static void RegisterRestApi(string api)
         {
-            _lastRestDelays[api] = new RestTimeOffset();
+            if (!_lastRestDelays.ContainsKey(api))
+                _lastRestDelays.TryAdd(api, new RestTimeOffset());
         }
 
         /// <summary>