Broker failed with error: task should not be deleted

[1505869986]

任务异常时 总是提示删除任务失败

worker setting
{"Broker":"127.0.0.1:6379","Lock":"","MultipleBrokerSeparator":"","DefaultQueue":"async","ResultBackend":"127.0.0.1:6379","ResultsExpireIn":3600,"AMQP":null,"SQS":null,"Redis
":{"MaxIdle":20,"MaxActive":0,"IdleTimeout":300,"Wait":false,"ReadTimeout":15,"WriteTimeout":15,"ConnectTimeout":15,"NormalTasksPollPeriod":1000,"DelayedTasksPollPeriod":500,"DelayedTasksKey":"","MasterName":""},"GCPPubSub":null,"MongoDB":null,"TLSConfig":null,"NoUnixSignals":false,"DynamoDB":null}