Should I exec "FASTJOB" or "ACKJOB" after I exec "GETJOB" ?

I add a job with "ADDJOB" in the disque.
localhost:7711> addjob test "yaya" 10000
the scrreen console that:
D-351c426f-BAZ7uyDERGtv7ybjIz/19a1A-05a1

then I exec the getjob ,I get this job.
I exec the command: qlen
the result returns 0 or empty

Whether I need to exec the "FASTJOB" or "ACKJOB" to GC this channel in disque after I exec "GETJOB"?