This is very odd, because it is a project which is deployed as a new app with no fly.toml nor Dockerfile or the likes existing.
We were under the impression that fly launch would perform all required steps, including setting up a database cluster (which presumably the volume is for), as this was the case in the past, when setting up other apps.
EDIT: It seems like the issues we encounter are the same as, or at least related to, Timeout on CreatePostgresCluster.app - #15 by tomgeene and Deploy errors: Post "https://api.fly.io/graphql": unexpected EOF - #11 by le_simon