diff --git a/xchange-stream-okex/src/main/java/info/bitrich/xchangestream/okex/OkexStreamingExchange.java b/xchange-stream-okex/src/main/java/info/bitrich/xchangestream/okex/OkexStreamingExchange.java
index aea9cf83e5a..dee0d964f95 100644
--- a/xchange-stream-okex/src/main/java/info/bitrich/xchangestream/okex/OkexStreamingExchange.java
+++ b/xchange-stream-okex/src/main/java/info/bitrich/xchangestream/okex/OkexStreamingExchange.java
@@ -66,8 +66,11 @@ private String getApiUrl() {
 
   @Override
   public Completable disconnect() {
-    streamingService.pingPongDisconnectIfConnected();
-    return streamingService.disconnect();
+    if(streamingService != null) {
+      streamingService.pingPongDisconnectIfConnected();
+      return streamingService.disconnect();
+    }
+    return null;
   }
 
   @Override