I am trying to set a log retention policy for loki so that the logs will be deleted after 28 days. I also want to set the query roll back to 28 days but no matter what I do , the limit stays : 30d1h

global:
  dnsService: "coredns"
loki:
  enabled: true
  isDefault: true
  auth_enabled: false
  url: http://{{(include "loki.serviceName" .)}}:{{ .Values.loki.service.port }}
  readinessProbe:
    httpGet:
      path: /ready
      port: http-metrics
    initialDelaySeconds: 45
  livenessProbe:
    httpGet:
      path: /ready
      port: http-metrics
    initialDelaySeconds: 45
  singleBinary:
    replicas: 1
  commonConfig:
    replication_factor: 1

backend:
  replicas: 1
read:
  replicas: 1
write:
  replicas: 1

minio:
  enabled: true

compactor:
  working_directory: /data/retention
  compaction_interval: 10m
  retention_enabled: true
  retention_delete_delay: 1m
  retention_delete_worker_count: 150
  delete_request_store: aws
schema_config:
    configs:
      - from: "2020-07-31"
        index:
            period: 24h
            prefix: index_
        object_store: aws
        schema: v13
        store: tsdb
storage_config:
  tsdb_shipper:
    active_index_directory: /data/index
    cache_location: /data/index_cache
  aws:
    s3:
      bucket_name: loki
limits_config:
  max_query_lookback: 672h # 28 days
  retention_period: 672h   # 28 days

I apply loki with command:
helm upgrade –install loki grafana/loki –values loki-values.yaml –set loki.useTestSchema=true

loki queries in grafana roll back to 28 days
and retention policy set to 28 days