{"status":"400","message":"Could not register with provided information"}

Question

I am trying to register a user into a SQL database using php. I am not sure why this message is popping up. {"status":"400","message":"Could not register with provided information"} This is what Im using in the url:http://localhost/iHertzmusic/register.php?username=Bob&password=1234&email=bob@mail.com&fullname=Bob%20John I it might be the url that is the problem but this worked before I add emailed conformation in STEP 4. Here is my register.php:

<?php

//Step 1. Delare parms of user info
// Sucuring information and storing variables
$username = htmlentities($_REQUEST["username"]);
$password = htmlentities($_REQUEST["password"]);
$email = htmlentities($_REQUEST["email"]);
$fullname = htmlentities($_REQUEST["fullname"]);

// if GET or POST are empty
if (empty($username) || empty($password) || empty($email) || empty($fullname)) {
  $returnArray["status"] = "400";
  $returnArray["massage"] = "Missing required information";
  echo json_encode($returnArray);
  return;

}

// secure password
$salt = openssl_random_pseudo_bytes(20);
$secured_password = sha1($password . $salt);

//Step 2. Build connection
//Secure way to build conn
$file = parse_ini_file("../../../iHertzmusic.ini");

// store in php var inf from ini var
$host = trim($file["dbhost"]);
$user = trim($file["dbuser"]);
$pass = trim($file["dbpass"]);
$name = trim($file["dbname"]);

// include access.php to call func from access.php file
require ("secure/access.php");
$access = new access($host, $user, $pass, $name);
$access->connect();

// Step 3. Insert user information
$result = $access->registerUser($username, $secured_password, $salt, $email, $fullname);

//Successfully registered
if ($result) {

    // got current registered user information and store in user
    $user = $access->selectUser($username);

    // declare information to feedback to user of App as json
    $returnArray["status"] = "200";
    $returnArray["message"] = "Successfully registered";
    $returnArray["id"] = $user["id"];
    $returnArray["username"] = $user["username"];
    $returnArray["email"] = $user["email"];
    $returnArray["fullname"] = $user["fullname"];

    // STEP 4. Emailing
    //include email.php

    require ("secure/email.php");
    // store all class in $email var
    $email = new email();

    // store generated token in $token var
    $token = $email->generateToken(20);

    //save in 'emailTokens' table
    $access->saveToken("emailTokens", $user["id"], $token);

    //refer emailing information
    $details = array();
    $details["subject"] = "Email confirmation on iHertz";
    $details["to"] = $user["email"];
    $details["fromName"] = "Sean O'Neal";
    $details["fromEmail"] = "ihertzmusic432@gmail.com";

    // access template file
    $template = $email->confirmationTemplate();

    // replace {token} from confirmationTemplate.html by $token and store all content in $template var
    $template = str_replace("{token}", $token, $template);

    $details["body"] = $template;

    $email->sendemail($details);

  } else { 

    $returnArray["status"] = "400";
    $returnArray["message"] = "Could not register with provided information";
}

// Step 5. Close connection
$access->disconnect();

// Step 6. Json data
echo json_encode($returnArray);

 ?>

Notice: Undefined variable: returnArray in

    // Select user information
     public function selectUser($username) {

    // sql command
    $sql = "SELECT * FROM users WHERE username'".$username."'";

    // assign result we got from $sql to $result var
    $result = $this->conn->query($sql);

    // if we have at least 1 result returned
    if ($result != null && (mysqli_num_rows($result) >= 1 )) {

      // assign result we got to $row as accociative array
      $row = $result->fetch_array(MYSQLI_ASSOC);

      if (!empty($row)) {
        $returnArray = $row;
      }
    }

    return $returnArray;
}

Notice: Undefined variable: charactersLength

function generateToken($length) {

  // some characters
  $characters = "qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM1234567890";

  // get length of characters string
  $characters = strlen($characters);

  $token = '';

  // generate random char from $characters every time until it is less than $charactersLength
  for ($i = 0; $i < $length; $i++) {
    $token .=$characters[rand(0, $charactersLength-1)];
   }

  return $token;

 }