Send Password reset link is not working (Expected response code 250 but got code "530",with message "530 5.7.1 Authentication required )

Given that you're getting "530 - Authentication required", I'd assume you have the route to the 'send password' endpoint somehow hidden behind your Auth middleware?

Perhaps you should post your routes/web.php file, or the output from: artisan route:list for us to take a look at...

@burlresearch

routes/web.php

Route::get('/', 'WelcomeController@show');

Route::get('/home', 'HomeController@index');
Route::resource('home', 'HomeController')->middleware('auth');


Route::get('training/{pid}/{questid}', 'TrainingController@show')->middleware('auth');
Route::get('training/{pid}/{questid}/start-quiz', 'TrainingController@startQuiz')->middleware('auth');
Route::put('training/{pid}/{questid}/evaluate', 'UserTrainingHistoryController@store')->middleware('auth');

Route::post('training/{pid}/{questid}/videoWatched', 'UserTrainingHistoryController@hasWatched')->middleware('auth');

Route::resource('training', 'TrainingController')->middleware('auth');

Route::get('presentation/{name}', 'ToolController@presentation')->middleware('auth');
Route::resource('tools', 'ToolController')->middleware('auth');

Route::get('branding/my_certificate/{id}', 'BrandingController@certificate')->middleware('auth');
Route::get('branding/download/{pid}/{id}', 'BrandingController@resource')->middleware('auth');
Route::resource('branding', 'BrandingController')->middleware('auth');

Route::get('workouts/{pid}/{categoryid}', 'WorkoutController@scripts')->middleware('auth');
Route::resource('workouts', 'WorkoutController')->middleware('auth');

Where is your Auth::routes() declaration? Did you run php artisan make:auth to provide your default Auth routes? This may be your whole issue.

Also, an alternative to cleanup your routing file may be to use a route-group (up to you, worth a mention):

<?php
Auth::routes();     // generated by `artisan make:auth`!!!

Route::get('/', 'WelcomeController@show');
Route::resource('home', 'HomeController');          // check constructor for 'auth' middleware

Route::middleware(['auth'])->group(function () {    // 'middleware group' can cleanup routing file
    Route::get('training/{pid}/{questid}', 'TrainingController@show');
    Route::get('training/{pid}/{questid}/start-quiz', 'TrainingController@startQuiz');
    Route::put('training/{pid}/{questid}/evaluate', 'UserTrainingHistoryController@store');

    Route::post('training/{pid}/{questid}/videoWatched', 'UserTrainingHistoryController@hasWatched');

    Route::resource('training', 'TrainingController');

    Route::get('presentation/{name}', 'ToolController@presentation');
    Route::resource('tools', 'ToolController');

    Route::get('branding/my_certificate/{id}', 'BrandingController@certificate');
    Route::get('branding/download/{pid}/{id}', 'BrandingController@resource');
    Route::resource('branding', 'BrandingController');

    Route::get('workouts/{pid}/{categoryid}', 'WorkoutController@scripts');
    Route::resource('workouts', 'WorkoutController');

});

Without Auth::routes() you may be missing the required predefined routes for your password-reset paths?

$ artisan route:list
...
| POST      | login                  | Auth\LoginController@login                        |
| GET|HEAD  | login                  | Auth\LoginController@showLoginForm                |
| POST      | logout                 | Auth\LoginController@logout                       |
| POST      | password/email         | Auth\ForgotPasswordController@sendResetLinkEmail  |
| POST      | password/reset         | Auth\ResetPasswordController@reset                |
| GET|HEAD  | password/reset         | Auth\ForgotPasswordController@showLinkRequestForm |
| GET|HEAD  | password/reset/{token} | Auth\ResetPasswordController@showResetForm        |
| GET|HEAD  | register               | Auth\RegisterController@showRegistrationForm      |
| POST      | register               | Auth\RegisterController@register                  |

@burlresearch I am using Spark, It comes with Auth setup already.

Auth::routes()

has been replaced in some other file and has been working just fine. The problem is something else

The reason I thought to look at routing, is that your error seems to indicate you are hitting a route, during password-reset, that is protected by Auth, and so that's why the reset emails cannot be sent.

If you think the error is with MailTrap auth - then you could simply test it with a quick artisan command...

I think your credentials are wrong - check those at MailTrap:

   Swift_TransportException  : Failed to authenticate on SMTP server with username "4ef9d5cd1dffd3" using 3 possible authenticators
.../Swift/Transport/Esmtp/AuthHandler.php: 181
  181:             throw new Swift_TransportException(
  182:                 'Failed to authenticate on SMTP server with username "'.
  183:                 $this->username.'" using '.$count.' possible authenticators'
  184:                 );
  185:         }
  186:     }

@burlresearch now the error is gone and I can see the email on MailTrap but I am unable to receive email on my real Gmail account. Am I doing something wrong here?

Great - glad to hear this problem is solved.

In order to actually send email out into the wild - you'll have to use one of the many other drivers that Laravel offers. That comes with a little more configuration, and a working SMTP account somewhere. Perhaps look over some of the options:

https://laravel.com/docs/5.6/mail#introduction

The entire point of MailTrap is that it does not send mail out, but rather 'traps' it, and shows you what would be sent.

thankyou very much @burlresearch