Laravel gmail smtp not sending email on live server

Question

I am working on a laravel project using laravel 8. In my project, I have setup gmail smtp and it's working perfectly fine on localhost (using wamp server) and mails are being sent to any desired email address. But when I upload the website on my live server, the mail functionality is not working with an error...

Swift_TransportException Connection could not be established with host smtp.gmail.com :stream_socket_client(): Unable to connect to tcp://smtp.gmail.com:587 (Network is unreachable)

I am using the same setup on live server as the localhost. However, I have been through a lots of other stackoverflow questions and their solutions, but none of these are helping. Can someone please help? FYI, I am using Dhaka Web Host server.

My .env setup

MAIL_MAILER=smtp
MAIL_HOST=smtp.gmail.com
MAIL_PORT=587
[email protected]
MAIL_PASSWORD=nquxojqqeldqafbl
MAIL_ENCRYPTION=tls
[email protected]
MAIL_FROM_NAME="${APP_NAME}"

My config/mail.php

<?php

return [

    'default' => env('MAIL_MAILER', 'smtp'),

    'mailers' => [
        'smtp' => [
            'transport' => 'smtp',
            'host' => env('MAIL_HOST', 'smtp.gmail.com'),
            'port' => env('MAIL_PORT', 587),
            'encryption' => env('MAIL_ENCRYPTION', 'tls'),
            'username' => env('MAIL_USERNAME'),
            'password' => env('MAIL_PASSWORD'),
            'timeout' => null,
            'auth_mode' => null,
        ],

        'ses' => [
            'transport' => 'ses',
        ],

        'mailgun' => [
            'transport' => 'mailgun',
        ],

        'postmark' => [
            'transport' => 'postmark',
        ],

        'sendmail' => [
            'transport' => 'sendmail',
            'path' => '/usr/sbin/sendmail -bs',
        ],

        'log' => [
            'transport' => 'log',
            'channel' => env('MAIL_LOG_CHANNEL'),
        ],

        'array' => [
            'transport' => 'array',
        ],
    ],

    /*
    |--------------------------------------------------------------------------
    | Global "From" Address
    |--------------------------------------------------------------------------
    |
    | You may wish for all e-mails sent by your application to be sent from
    | the same address. Here, you may specify a name and address that is
    | used globally for all e-mails that are sent by your application.
    |
    */

    'from' => [
        'address' => env('MAIL_FROM_ADDRESS', '[email protected]'),
        'name' => env('MAIL_FROM_NAME', 'Example'),
    ],

    /*
    |--------------------------------------------------------------------------
    | Markdown Mail Settings
    |--------------------------------------------------------------------------
    |
    | If you are using Markdown based email rendering, you may configure your
    | theme and component paths here, allowing you to customize the design
    | of the emails. Or, you may simply stick with the Laravel defaults!
    |
    */

    'markdown' => [
        'theme' => 'default',

        'paths' => [
            resource_path('views/vendor/mail'),
        ],
    ],

];

I tried to change the MAIL_MAILER=smtp to MAIL_MAILER=sendmail, I have also tried to edit config/mail.php with various suggestions. I have also tried to change the MAIL_PORT and MAIL_ENCRYPTION according to suggestions I found. Nothing worked. But on localhost, my general setup is working perfectly and sending mails.