Php laravel队列主管工作人员给出异常

我正在为我的Laravel项目中的队列工作事件运行服务器上的主管。主管对于排队的作业非常有效，但当我检查worker.log文件时，每秒都会发生异常。例外是

   ErrorException 

  A non well formed numeric value encountered

  at /var/www/html/mySampleProject/vendor/laravel/framework/src/Illuminate/Queue/Worker.php:729
    725â–•     {
    726â–•         if ($seconds < 1) {
    727â–•             usleep($seconds * 1000000);
    728â–•         } else {
  ➜ 729▕             sleep($seconds);
    730â–•         }
    731â–•     }
    732â–• 
    733â–•     /**

      [2m+17 vendor frames [22m
  18  /var/www/html/mySampleProject/artisan:37
      Illuminate\Foundation\Console\Kernel::handle()

我还没有找到任何解决办法。请帮忙。提前谢谢

[program:queue-worker]
process_name=%(program_name)s_%(process_num)02d
command=php /var/www/html/mySampleProject/artisan queue:work database --sleep=3 --tries=3
autostart=true
autorestart=true
user=ubuntu
numprocs=2
redirect_stderr=true
stdout_logfile=/var/www/html/mySampleProject/storage/logs/worker.log