captcha and validate can't work at the same time about captcha HOT 2 CLOSED

            $validate_messages = [
                'username.required' =>  "Account can't be blank.",
                'password.required' =>  "Password can't be blank.",
                'captcha.required' => "Validate code can't be blank.",
                'captcha.captcha' => "Validate code incorrect.",
            ];

            $this->validate($request, [
                'username'     => 'required',
                'password'     => 'required',
                'captcha' => 'required|captcha',
            ], $validate_messages);

            if ($this->validate->fails()) {
                return redirect('admin/login')->withInput()->withErrors($this->validator);
            }