kedaAutoscaling not scaling with mimir-distributed helm chart

[lpaturel]

Hello,
I'm currently trying to set up autoscaling on my Mimir instance using the mimir-ditributed helm chart.
My current query-frontend configuration is as such ->

  replicas: 1
  nodeSelector:
    nodepool: mimir-nodepool
  kedaAutoscaling:
    enabled: true
    minReplicaCount: 1
    maxReplicaCount: 3
    targetCPUUtilizationPercentage: 60
    targetMemoryUtilizationPercentage: 90
    behavior:
      scaleDown:
        policies:
          - periodSeconds: 60
            type: Percent
            value: 10

As far as I understand, the helm chart creates a ScaledObject with the following triggers ->

triggers:
  - metadata:
      query: max_over_time(sum(sum by (pod) (rate(container_cpu_usage_seconds_total{container="query-frontend",namespace="default"}[5m]))
        and max by (pod) (up{container="query-frontend",namespace="default"}) >
        0)[15m:]) * 1000
      serverAddress: http://prometheus-server.default.svc.cluster.local:9090
      threshold: "150"
    type: prometheus
  - metadata:
      query: max_over_time(sum((sum by (pod) (container_memory_working_set_bytes{container="query-frontend",namespace="default"})
        and max by (pod) (up{container="query-frontend",namespace="default"}) >
        0) or vector(0))[15m:]) + sum(sum by (pod) (max_over_time(kube_pod_container_resource_requests{container="query-frontend",namespace="default",
        resource="memory"}[15m])) and max by (pod) (changes(kube_pod_container_status_restarts_total{container="query-frontend",namespace="default"}[15m])
        > 0) and max by (pod) (kube_pod_container_status_last_terminated_reason{container="query-frontend",namespace="default",
        reason="OOMKilled"}) or vector(0))
      serverAddress: http://prometheus-server.default.svc.cluster.local:9090
      threshold: "483183820"
    type: prometheus

But I can't get it to work :/
I've tried the queries 1 by 1 inside Grafana and the following part gives me a hard time as I'm missing the "container" label ->

up{container="query-frontend",namespace="default"}

Where is this metric supposed to come from ? Is there anything to deploy first?

If anyone has a clue, I'd love to hear about it ;)
Thanks in advance