Sometime, the workflow stuck and not processing.
Please check this repo https://github.com/zsinryu/laravel-workflow-parallel

1. Clone .env.example to .env
2. ./vendor/bin/sail up
3. Open 3 terminals, 2 for php artisan queue:work for simulate multi workers. And use the last terminal for test command php artisan workflow:test
4. There are about 30% percent the error will happen. So try to run the test command few times.