Login

Jeg har et udfordring med denne. Da denne side var færdig så skulle den indputte brugernavn og password i dB men den fejler at den ikke kan finde signup.php. Der hvor den virker er til hvor den skal tjekke user navn og mail derefter kan jeg ikke se fejlen. Er der nogle kan se fejle

<?php
if(isset($_POST['signup-submit'])){

require 'dbh.inc.php';

$username = $_POST['uid'];
$email = $_POST['mail'];
$password = $_POST['pwd'];
$passwordRepeat = $_POST['pwd-repeat'];

if(empty($username) || empty($email) || empty($password) || empty($passwordRepeat)){
    header("Location: ../signup.php?error=emtyfields&uid=".$username. "&mail=".$email);
    exit();
    }
    else if(!filter_var($email, FILTER_VALIDATE_EMAIL) && !preg_match("/^[a-zA-Z0-9]*$/", $username)){
        header("Location: ../signup.php?error=invalidmailuid");
        exit();
    }
else if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
    header("Location: ../signup.php?error=invalidmail&uid=".$username);
        exit();
    }
else if (!preg_match("/^[a-zA-Z0-9]*$/", $username)) {
        header("Location: ../signup.php?error=invaliduid&mail=".$email);
        exit();
    }
else if(password !== $passwordRepeat){
        header("Location: ../signup.php?error=passwordcheckuid=".$username. "&mail=".$email);
        exit(); 
    }
else {

    $sql = "SELECT uidUsers FROM users WHERE uidUsers=?";
    $stmt = mysqli_stmt_init($conn);
    if (!mysql_stmt_prepare($stmt, $sql)){
        header("Location: ../signup.php?error=sqlerror");
        exit();

    }
else {
    mysqli_stmt_bind_param($stmt, "s", $username);
    mysqli_stmt_execute($stmt);
    mysqli_stmt_store_result($stmt);
    $resultCheck = mysqli_stmt_num_rows($stmt);
    if ($resultCheck > 0){
        header("Location: ../signup.php?error=usertaken&mail=" .$email);
        exit();
    }
    else {
        $sql = "INSERT INTO users (uidUsers, emailUsers, pwdUsers) VALUES (?, ?, ?)";
        $stmt = mysqli_stmt_init($conn);
        if (!mysql_stmt_prepare($stmt, $sql)){
            header("Location: ../signup.php?error=sqlerror");
            exit();
        }
        else{
        $hashedPwd = password_hash($password, PASSWORD_DEFAULT);
        mysqli_stmt_bind_param($stmt, "sss", $username, $email, $hashedPwd);
        mysqli_stmt_execute($stmt);
        header("Location: ../signup.php?signup=success");
            exit();

            }

        }

        }


    }
    mysqli_stmt_close($stmt);
    musqli_close($conn);

}
else{
    header("Location: ../signup.php");
    exit(); 
}