diff --git a/includes/class-request.php b/includes/class-request.php
index e27bfe1..259af0f 100755
--- a/includes/class-request.php
+++ b/includes/class-request.php
@@ -34,7 +34,7 @@ public function __construct( $data ) {
 	 * @return string
 	 */
 	private function create_expected_signature() {
-		return base64_encode( hash_hmac( 'sha1', json_encode( $this->data ), self::$secret_key, true ) );
+		return base64_encode( hash_hmac( 'sha1', json_encode( $this->data, JSON_UNESCAPED_UNICODE ), self::$secret_key, true ) );
 	}
 
 	/**
@@ -69,4 +69,4 @@ public function get_signed_url( $action = '' ) {
 	}
 
 
-}
\ No newline at end of file
+}