Can't deploy Redis instance

I have followed the guide verbatim to deploy a Redis instance using the Redis Docker image. The only difference is I named my volume redis_service which I assume is not a problem since the name matches in my fly.toml and shows up when I run fly volumes list.

The deployment eventually fails with:

 1 desired, 1 placed, 0 healthy, 1 unhealthy
--> v1 failed - Failed due to unhealthy allocations - no stable job version to auto revert to and deploying as v2

--> Troubleshooting guide at
Error abort

Is there perhaps something missing from the guide? Any tips what could be wrong? I read about how this error can happen due to ports but since this is really just the generated fly.toml file with an added volume mount, it doesn’t seem like there should be anything wrong.