Elastic search sink Connector from kafka

I had built an elastic search sink connector from the confluent connector hub community. Build a docker image using that image my connect is working fine but when I am trying to connect Elastic search using this connector getting the below issue. A verified user id and password is working fine while connecting to elastic search manually using those.

Could not connect to Elasticsearch. Error message: PKIX path building
failed: sun.security.provider.certpath.SunCertPathBuilderException:
unable to find valid certification path to requested target

    Could not authenticate the user. Check the 'connection.username' and
    'connection.password'. Error message: PKIX path building failed:
    sun.security.provider.certpath.SunCertPathBuilderException: unable to
    find valid certification path to requested target

    Could not authenticate the user. Check the 'connection.username' and
    'connection.password'. Error message: PKIX path building failed:
    sun.security.provider.certpath.SunCertPathBuilderException: unable to
    find valid certification path to requested target. Also added 
    elastic.security.protocol : PLAINTEXT property to ship cerificate.

Configuration YAML is below
apiVersion: kafka.strimzi.io/v1alpha1
kind: KafkaConnector
metadata:
labels:
strimzi.io/cluster: vcc-esp-connect
name: vcc-elasticsearch-connector
spec:
class: io.confluent.connect.elasticsearch.ElasticsearchSinkConnector
config:
connection.url: “https://XXXXXX.net
elastic.security.protocol : PLAINTEXT
key.ignore: true
connection.username: kafka_esp
connection.password: #######
schema.ignore: true
topic.index.map: “icoe-int:cust_id”
topics: shared-matrics-topic
type.name: kafka-connect
value.converter: org.apache.kafka.connect.json.JsonConverter
tasksMax: 2