Knative Eventing, KafkaSource kind doesn't read messages from the earliest commit

Question

I deployed a Knative Eventing, KafkaSource kind resource in our namespace. I have set the spec **spec.initialOffset: earliest **. But it still is only pulling the latest messages. It doesn't seem to be reading messages from the oldest commit point. Is there something I'm doing wrong? Here is the yaml file,

apiVersion: sources.knative.dev/v1beta1
kind: KafkaSource
metadata:
  name: kafka-sample-dev
  namespace: sample-dev
  labels:
    kafkasources.sources.knative.dev/key-type: byte-array
spec:
  bootstrapServers:
  - kaas-prod-v1-kafka:16562  
  consumerGroup: sample-04172023
  initialOffset: earliest
  net:
   tls:
     enable: true
     cert:
       secretKeyRef:
         key: tls.crt
         name: kaas-tls-secret-prd
     key:
       secretKeyRef:
         key: tls.key
         name: kaas-tls-secret-prd
     caCert:
       secretKeyRef:
         key: ca.crt
         name: kaas-ca-secret-prd
  sink:
    ref:
      apiVersion: serving.knative.dev/v1
      kind: Service
      name: sample-funqy-quarkus-svc
  topics:
  - prd.canonical.topic16

on setting the spec property as spec.initialOffset: earliest , I am expecting the kafkasource to start reading the messages from the earliest commit point. But it doesn't seem to be doing this.