diff --git a/com_oauthserver/administrator/src/Model/ClientModel.php b/com_oauthserver/administrator/src/Model/ClientModel.php
index b9967bf..5de527d 100644
--- a/com_oauthserver/administrator/src/Model/ClientModel.php
+++ b/com_oauthserver/administrator/src/Model/ClientModel.php
@@ -68,12 +68,14 @@ class ClientModel extends AdminModel
             $data = $this->getItem();
         }
 
-        $root = Uri::root();
-        $uri  = new Uri($root);
+        if ($data)
+        {
+            $uri = new Uri(Uri::root());
 
-        $data->def('authorize_url', (string) $uri->setPath('login/oauth/authorize'));
-        $data->def('token_url', (string) $uri->setPath('login/oauth/token'));
-        $data->def('profile_url', (string) $uri->setPath('login/oauth/profile'));
+            $data->def('authorize_url', (string) $uri->setPath('login/oauth/authorize'));
+            $data->def('token_url', (string) $uri->setPath('login/oauth/token'));
+            $data->def('profile_url', (string) $uri->setPath('login/oauth/profile'));
+        }
 
         $this->preprocessData('com_oauthserver.client', $data);
 
@@ -82,17 +84,14 @@ class ClientModel extends AdminModel
 
     public function validate($form, $data, $group = null): bool|array
     {
+        // Since the client’s identifier and secret key are created on the server and completely
+        // exclude the user’s influence on their value, we remove them from the request to eliminate
+        // any possibility of substitution of this data.
         unset($data['identifier'], $data['secret']);
-        unset($data['authorize_url'], $data['token_url'], $data['profile_url']);
 
         return parent::validate($form, $data, $group);
     }
 
-    public function save($data)
-    {
-        return parent::save($data); // TODO: Change the autogenerated stub
-    }
-
     /**
      * @param   ClientTable  $table
      *
@@ -102,38 +101,42 @@ class ClientModel extends AdminModel
      */
     protected function prepareTable($table): void
     {
-        $app   = Factory::getApplication();
-        $input = $app->getInput();
-        $task  = strtolower($input->getCmd('task', ''));
+        $app = Factory::getApplication();
 
-        if (empty($table->id))
+        if ($table->id > 0)
         {
             $table->identifier = $this->generateNewIdentifier();
         }
 
-        if ($task === 'save2reset' || empty($table->id))
+        if (empty($table->secret)
+            && !$table->public
+            && ($table->id > 0 || $app->getInput()->get('task') == 'save2reset'))
         {
-            $table->secret = '';
+            $table->secret = $this->generateNewSecret();
         }
 
-        if (!!$table->public)
+        if ($table->public)
         {
             $table->secret = '';
         }
-        else
-        {
-            if (empty($table->secret))
-            {
-                $table->secret = $this->generateNewSecret();
-            }
-        }
 
         $table->name = htmlspecialchars_decode($table->name, ENT_QUOTES);
 
         parent::prepareTable($table);
     }
 
-    protected function generateNewHash($field, $algo = 'sha256', $length = 16)
+    /**
+     * Generate a hash value of string for table field and check it unique
+     *
+     * @param   string  $field
+     * @param   string  $algo
+     * @param   int     $length
+     *
+     * @return string
+     * @throws \Exception
+     * @since version
+     */
+    protected function generateNewHash(string $field, string $algo = 'sha256', int $length = 16): string
     {
         $hash  = hash($algo, Crypt::genRandomBytes($length));
         $table = $this->getTable();
@@ -146,11 +149,25 @@ class ClientModel extends AdminModel
         return $hash;
     }
 
+    /**
+     * Generate unique hash value for client identifier
+     *
+     * @return string
+     * @throws \Exception
+     * @since version
+     */
     protected function generateNewIdentifier(): string
     {
         return $this->generateNewHash('identifier', 'md5');
     }
 
+    /**
+     * Generate unique hash value for client secret key
+     *
+     * @return string
+     * @throws \Exception
+     * @since version
+     */
     protected function generateNewSecret(): string
     {
         return $this->generateNewHash('secret', 'sha512', 32);