Fatal error: Uncaught Error: Class "Illuminate\Database\Migrations\Migration" not found in D:\Apache24\www\api.print.nxytec.cn\back\database\migrations\2022_09_01_053001_create_billnum_table.php:7 Stack trace: #0 {main} thrown in D:\Apache24\www\api.print.nxytec.cn\back\database\migrations\2022_09_01_053001_create_billnum_table.php on line 7