Volume is not getting deleted while deleting the instance even checked "Delete on instance termination" while creating the instance

Using Openstack Provider with hammer-10 appliance image
I have provision an instance from manageiq UI(hammwer-10), while creating instance i have added a volume and selected checkbox “DELETE ON INSTANCE TERMINATION”
but after deletion the instance it is not deleting the attached volume as i have selected “DELETE ON INSTANCE TERMINATION”
any idea or help?