Gentoo contextualization

I have a gentoo image that started its life as openstack stage 4 image using diskimage-builder
I used “” and it seems to work properly except for two things.
It doesnt seem to install my ssh keys (tho I might be missing something I dont know how to troubleshoot that yet) and the second, the biggie the partition does not expand on startup. I started with a 6 gig image, Spin up a new VM and tell it us 20 gigs. fdisk /dev/vda and it shows /dev/vda at 20 gigs but /dev/vda1 is still at 6 gigs. Am I missing something?

Versions of the related components and OS (frontend, hypervisors, VMs):
Gentoo OS on frontend and host, hypervisor KVM

Steps to reproduce:

Current results:

Expected results: