Fatal error: Uncaught Error: Class "Tests\TestCase" not found in C:\xampp\htdocs\bilipoa\tests\Feature\SubscriberListSplitsPerDeviceTest.php:30 Stack trace: #0 {main} thrown in C:\xampp\htdocs\bilipoa\tests\Feature\SubscriberListSplitsPerDeviceTest.php on line 30