please try these
<form action="Delegate_update.php" method="post">
Name
<input type="text" name= "Name" value= "<?php echo $row['Name']; ?> "size=10>
Username
<input type="text" name= "User_name" value= "<?php echo $row['User_name']; ?> "size=10>
Password
<input type="text" name= "User_password" value= "<?php echo $row['User_password']; ?>" size=17>
<input type="submit" name= "submit" value="Update">
</form>