Drupal ignoring changes to settings.php
Check with including namespace.  Also, check if any other code override configuration or do you enabled settings.local.php. Add this code to the bottom of settings.php

 $databases['default']['default'] = array (
  'database' =&gt; 'my_db_database',
  'username' =&gt; 'my_db_user',
  'password' =&gt; 'my_db_password',
  'prefix' =&gt; '',
  'host' =&gt; 'localhost',
  'port' =&gt; '3306',
  'namespace' =&gt; 'Drupal\\Core\\Database\\Driver\\mysql',
  'driver' =&gt; 'mysql',
);