diff --git a/src/RestClient.php b/src/RestClient.php
index fa32ec3..75a5e19 100644
--- a/src/RestClient.php
+++ b/src/RestClient.php
@@ -224,6 +224,7 @@ class RestClient {
             // Set option to write response to a file
             $fileHandle = fopen($this->downloadFilename, 'w');
             curl_setopt($ch, CURLOPT_FILE, $fileHandle);
+            $this->downloadFilename = null;
         }
 
         $response = curl_exec($ch);