diff --git a/.gitignore b/.gitignore
index 4c8b545..0f205a6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -45,3 +45,4 @@ Temporary Items
 .idea
 vendor
 composer.lock
+.phpunit.result.cache
\ No newline at end of file
diff --git a/README.md b/README.md
index 51a6b21..6416a73 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,17 @@
+# How to use this fork as zarinpal/zarinpal
+* Fork this repository and add this code to your composer.json
+```
+"repositories": [
+        {
+            "type": "vcs",
+            "url":"https://github.com/<Your_GitHub_Username>/zarinpal-composer-library"
+        }
+    ],
+```
+ * Append `"zarinpal/zarinpal": "dev-master"` to `"require"`
+ * Execute command `composer update`
+ * Generate GitHub Token key (open link that printed in console by composer for token generating)
+ * Enter Token and Done!
 # zarinpal-composer-library 
 [![Build Status](https://travis-ci.org/RTLer/zarinpal-composer-library.svg?branch=master)](https://travis-ci.org/RTLer/zarinpal-composer-library) 
 [![StyleCI](https://styleci.io/repos/37937280/shield)](https://styleci.io/repos/37937280)
diff --git a/composer.json b/composer.json
index 8237228..4ae5e10 100644
--- a/composer.json
+++ b/composer.json
@@ -10,11 +10,12 @@
     ],
     "minimum-stability": "stable",
     "require": {
-        "guzzlehttp/guzzle": "^6.2"
+        "php": "^7.3|^8.0",
+        "guzzlehttp/guzzle": "^7.0.1"
     },
     "require-dev": {
-        "phpunit/phpunit": "6.3.*",
-        "satooshi/php-coveralls": "^1.0"
+        "php-coveralls/php-coveralls": "^2.4",
+        "phpunit/phpunit": "^9.3.3"
     },
     "autoload": {
         "psr-4": {
diff --git a/src/Zarinpal.php b/src/Zarinpal.php
index 4c60a5d..358c96a 100644
--- a/src/Zarinpal.php
+++ b/src/Zarinpal.php
@@ -7,7 +7,7 @@
 
 class Zarinpal
 {
-    private $redirectUrl = 'https://www.zarinpal.com/pg/StartPay/%u';
+    private $redirectUrl = 'https://www.zarinpal.com/pg/StartPay/%s';
     private $merchantID;
     private $driver;
     private $Authority;
@@ -91,7 +91,7 @@ public function verify($amount, $authority)
 
     public function redirect()
     {
-        header('Location: '.sprintf($this->redirectUrl, $this->Authority));
+        header('Location: '.$this->makeRedirectURL($this->Authority));
         die;
     }
 
@@ -100,7 +100,11 @@ public function redirect()
      */
     public function redirectUrl()
     {
-        return sprintf($this->redirectUrl, $this->Authority);
+        return $this->makeRedirectURL($this->Authority);
+    }
+
+    public function makeRedirectURL($Authority){
+        return sprintf($this->redirectUrl, $Authority);
     }
 
     /**
@@ -116,7 +120,7 @@ public function getDriver()
      */
     public function enableSandbox()
     {
-        $this->redirectUrl = 'https://sandbox.zarinpal.com/pg/StartPay/%u';
+        $this->redirectUrl = 'https://sandbox.zarinpal.com/pg/StartPay/%s';
         $this->getDriver()->enableSandbox();
     }