Instantiate Openstack VMs on MAAS

Hello, I have the following scenario:
I deployed MAAS (version 2.6.2) on an Openstack VM.
I follow this tutorial (tutorial), to create a new “diskless” image to enable OpenStack VM to PXE boot.
I was able to enlist and commission the VM.
But I’m having a problem when I try to bootstrap the JUJU controller onto that VM because when I boot it up it doesn’t PXE boot, instead it boot up Ubuntu 18.04.

So I am only able to Enlist and Commission the VMs I can’t deploy and image through MAAS.
And I don’t know why this is happening.
Can anyone help?