diff --git a/lib/services/header/index.js b/lib/services/header/index.js
index 5a586919..154409e9 100644
--- a/lib/services/header/index.js
+++ b/lib/services/header/index.js
@@ -533,8 +533,10 @@ HeaderService.prototype._onHeadersSave = function(callback) {
   }
 
   //SZ: clear the interval check as sync is completed
-  if(self._syncCheckInterval)
+  if(self._syncCheckInterval){
     clearInterval(self._syncCheckInterval); 
+    self._syncCheckInterval = null;
+  }
 
   self._endHeaderSubscription(); // we don't need headers any more
   self._startBlockSubscription(); // we need new blocks coming tu us aynchronuously