trying to create one plugin getting soem issue to submit the array data in wordpress database.

$formDATA gets the array value now issue is when 
        $sql = "INSERT INTO `".$table_name ."` (`paid_arr`) VALUES '".$formDATA."'";
 
       $result  = $wpdb->insert($table_name,$formDATA);

getting strange warnings and errros not able to insert data in wp DB.

      Warning: array_keys() expects parameter 1 to be array, string given in /home3/mahesh/public_html/project/lal/wp-includes/wp-db.php on line 1316

     Warning: Invalid argument supplied for foreach() in /home3/mahesh/public_html/project/lal/wp-includes/wp-db.php on line 1318

      Warning: implode() [function.implode]: Invalid arguments passed in /home3/mahesh/public_html/project/lal/wp-includes/wp-db.php on line 1327


here is  php code;       

       $formDATA = array(
 
        'fname' => $fname,
        'lname' => $lname,
         'email' => $paidemail,
         'Phone' => $paidphone,
	 'gender' => $gender,
	  'hobbies' => $interest,
	  'hear' => $city,
	  'message' => $message_field,
	  'time' => $curtime
	 
 
        );
 
 
 
 
       formsubmitpaid($formDATA);       


      function formsubmitpaid($formDATA)
      {
      global $wpdb;

       $formDATA = json_encode($formDATA);

       $table_name = $wpdb->prefix . "padi_forms";
 
      $sql = "INSERT INTO `".$table_name ."` (`paid_arr`) VALUES '".$formDATA."'";
 
      $result  = $wpdb->insert($table_name,$formDATA);
 
      if(!$result){
    
       echo '<script>alert("dfdf")</script>';
 
       }
       else{
       echo '<script>alert("No")</script>';
 
 
        }
       print_r($sql);
       print_r($result);
 
       }