Laravel - SQL Server connection fail for user "sa" - php

Question

I'm trying to learn more about Laravel framework but get stuck on the database connection issue.
I already double-check the hostname, database name, username and the password and it's all correct. But when i try to do php artisan migrate function in my composer, it shows the error like this
SQLSTATE[28000]: [Microsoft][ODBC Driver 11 for SQL Server][SQL Server]Login failed for user 'sa'.
I don't know why is this happened, I try connecting the database using pure PHP syntax too and there's no problem. Could somebody explain ? I appreciates for any kind of information from here. Thanks a lot before..
Here is my .env file :
DB_CONNECTION=sqlsrv
DB_HOST=NDUT-PC\SQLEXPRESS
DB_DATABASE=SampleDB
DB_USERNAME=sa
DB_PASSWORD=48a365b4ce1e322a55ae9017f3daf0c0
And here is my database.php file :
<?php
return [
'default' => env('DB_CONNECTION', 'sqlsrv'),
'connections' => [
'sqlite' => [
'driver' => 'sqlite',
'database' => env('DB_DATABASE', database_path('database.sqlite')),
'prefix' => '',
],
'mysql' => [
'driver' => 'mysql',
'host' => env('DB_HOST', '127.0.0.1'),
'port' => env('DB_PORT', '3306'),
'database' => env('DB_DATABASE', 'forge'),
'username' => env('DB_USERNAME', 'forge'),
'password' => env('DB_PASSWORD', ''),
'unix_socket' => env('DB_SOCKET', ''),
'charset' => 'utf8mb4',
'collation' => 'utf8mb4_unicode_ci',
'prefix' => '',
'strict' => true,
'engine' => null,
],
'pgsql' => [
'driver' => 'pgsql',
'host' => env('DB_HOST', '127.0.0.1'),
'port' => env('DB_PORT', '5432'),
'database' => env('DB_DATABASE', 'forge'),
'username' => env('DB_USERNAME', 'forge'),
'password' => env('DB_PASSWORD', ''),
'charset' => 'utf8',
'prefix' => '',
'schema' => 'public',
'sslmode' => 'prefer',
],
'sqlsrv' => [
'driver' => 'sqlsrv',
'host' => env('DB_HOST', 'localhost'),
'port' => env('DB_PORT', '1433'),
'database' => env('DB_DATABASE', 'forge'),
'username' => env('DB_USERNAME', 'forge'),
'password' => env('DB_PASSWORD', ''),
'charset' => 'utf8',
'prefix' => '',
],
],
'migrations' => 'migrations',
'redis' => [
'client' => 'predis',
'default' => [
'host' => env('REDIS_HOST', '127.0.0.1'),
'password' => env('REDIS_PASSWORD', null),
'port' => env('REDIS_PORT', 6379),
'database' => 0,
],
],
];