I am running a 'guix system vm' and 'guix package -i' fails ...

g1@server17 ~$ guix package -i icecat
guix package: error: build failed: opening lock file
`/gnu/store/4iznqdzql2cp4l2jkr09jn10xxw861c4-mirrors.lock': Read-only
file system

Any idea what I am doing wrong? Here are the details ...

guix system vm -M 4 -c 4 /home/g1/src/vm/vms/server17/server17.scm

sudo /gnu/store/1vnsn52grzvpzrdndv1f3nkf7mdwd5wk-run-vm.sh -name
server17 -net
tap,ifname=server17,script=/home/g1/src/vm/qemu-ifup,downscript=/home/g1/src/vm/qemu-ifdn
-daemonize -display none

TIA - George