Loop snapshots are not automatically deleted

[li jerry]

Hi,ALL

     I created a loop snapshot on cloudstack 4.11.2 +CEPH 10.2.11.Execute at 3 
am every day, keep 3 copies.After a period of observation, I found that the 
snapshot on cloudstack always shows 3 copies.However, ceph found that the 
snapshot on rbd is added every day and never deleted.