firebaseのCannot find 'Auth' in scopeを治したい

解決したいこと

https://www.youtube.com/watch?v=KEvA0sSpOMo&t=75sこの動画を見ながらやり８分３５秒のところで実行しようとしたのですがAuth.auth().createUser...のAuthに赤線が引かれてCannot find 'Auth' in scopeとエラーが出たのですがどうすれば解決しますか？

試したこと

ターミナルでpod updeteと再度打ち直した

コード（ViewController側）


import UIKit
import Firebase

class ViewController: UIViewController {

    @IBOutlet weak var emailTextField: UITextField!
    @IBOutlet weak var passwordTextField: UITextField!
    @IBOutlet weak var usernameTextField: UITextField!
    @IBOutlet weak var registerButton: UIButton!
    @IBAction func tappedRegisterButton(_ sender: Any) {
        handleAuthToFierbase()
        
    }
    
    private func handleAuthToFierbase() {
        guard let email = emailTextField.text else {return}
        guard let password = passwordTextField.text else {return}
        
        Auth.auth().createUser(withEmail: email, password: password) { (res, err)  in　
 if let err = err {
                print("認証情報の保存に失敗しました。(err)")
                return
            }
            print("認証情報の保存に成功しました。")
            
        }
        
    }
    
    
    override func viewDidLoad() {
        super.viewDidLoad()


        registerButton.layer.cornerRadius = 20
        
        emailTextField.delegate = self
        passwordTextField.delegate = self
        usernameTextField.delegate = self
        
        NotificationCenter.default.addObserver(self, selector: #selector(showKeyboard), name: UIResponder.keyboardWillShowNotification, object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(hideKeyboard), name: UIResponder.keyboardDidHideNotification, object: nil)
        
    }
    
    @objc func showKeyboard(notitfication: Notification) {
        let keyboardFrame = (notitfication.userInfo![UIResponder.keyboardFrameEndUserInfoKey] as AnyObject).cgRectValue
            
        guard let KeyboardMinY = keyboardFrame?.minY else {return}
        let registerButtonMaxY = registerButton.frame.maxY
        let distance = registerButtonMaxY - KeyboardMinY + 20
        
        let tranceForm = CGAffineTransform(translationX: 0, y: -distance)
        
        UIView.animate(withDuration: 0.5, delay: 0, usingSpringWithDamping: 1, initialSpringVelocity: 1, options: [], animations: {
            
            self.view.transform = tranceForm
        })

    }
    
    @objc func hideKeyboard() {
        UIView.animate(withDuration: 0.5, delay: 0, usingSpringWithDamping: 1, initialSpringVelocity: 1, options: [], animations: {
            
            self.view.transform = .identity
        })
        
    }
    
    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
        
        self.view.endEditing(true)
    }
    
}

extension ViewController: UITextFieldDelegate {
    
    func textFieldDidChangeSelection(_ textField: UITextField) {
        let emailIsEmpty = emailTextField.text?.isEmpty ?? true
        let passwordIsEmpty = passwordTextField.text?.isEmpty ?? true
        let usernameIsEmpty = usernameTextField.text?.isEmpty ?? true
        
        if emailIsEmpty || passwordIsEmpty || usernameIsEmpty {
            registerButton.isEnabled = false
            registerButton.tintColor = UIColor.init(red: 255 / 255, green: 221 / 255, blue: 187 / 255, alpha: 1)
            
        } else {
            registerButton.isEnabled = true
            
        }
        
        print("textField.text: " , textField.text)
    }
}

コード（Podfile側）

target 'timefirebase' do
  # Comment the next line if you don't want to use dynamic frameworks
  use_frameworks!

  # Pods for timefirebase
pod 'Firebase/Analytics'
pod 'Firebase/Auth'
pod 'Firebase/Firestore'

  target 'timefirebaseTests' do
    inherit! :search_paths
    # Pods for testing
  end

  target 'timefirebaseUITests' do
    # Pods for testing
  end

end