There seems to be a recently introduced package name conflict.
There are two packages named "helm". One is is the package manager for Kubernetes and the other is a synthesizer. I noticed after upgrading and helm suddenly jumped from 0.9.0 to 3.12.3. `guix install email@example.com` restores helm-lv2 as a temp fix.
I suggest the latter be renamed "helm-lv2" to fix the issue.