PHP 注册修复

我试图使这项工作正确，但是当我输入密码并重复密码并按提交时，它告诉我它们不匹配（当我确实使它们匹配时），我一直在查找此代码部分中的错误，但找不到它。我什至没有到达它告诉我字符长度是短或长的部分，它总是卡在"密码不匹配"上。

<?php
 echo "<h1>Register</h1>";
//form data
$submit = $_POST['submit'];
$fullname = strip_tags($_POST['fullname']);
$username = strip_tags($_POST['username']);
$password = strip_tags($_POST['password']);
$repeatpassword =strip_tags($_POST['repeatpassword']);
$date = date("Y-m-d");
if ($submit)
{
//checks if all is filled
if ($fullname&&$username&&$password&&$repeatpassword)
        {
                    $passowrd = md5($password);
                    $repeatpassword = md5($repeatpassword);

                    if($password==$repeatpassword)
                    {
                    //length of username
                        if(strlen(username)>25||strlen($fullname)>25)
                        {
                        echo "username/fullname too long";
                        }
                        else
                        {
                        //check password length
                            if(strlen($password)>25||strlen($password)<6)
                            {
                            echo "password needs to be from 6 to 25!";
                            }
                            else
                                {
                                //register user
                                }
                        }
                    }
                    else
                    {
                    echo "password dose not match";
                    }
    }
else
echo "please fill out <b>all</b> fields!";
 }
?>