diff --git a/pulsar-io/kafka-connect-adaptor/src/main/java/org/apache/pulsar/io/kafka/connect/AbstractKafkaConnectSource.java b/pulsar-io/kafka-connect-adaptor/src/main/java/org/apache/pulsar/io/kafka/connect/AbstractKafkaConnectSource.java
index 3901c5f3d176b..5bd85a00f1762 100644
--- a/pulsar-io/kafka-connect-adaptor/src/main/java/org/apache/pulsar/io/kafka/connect/AbstractKafkaConnectSource.java
+++ b/pulsar-io/kafka-connect-adaptor/src/main/java/org/apache/pulsar/io/kafka/connect/AbstractKafkaConnectSource.java
@@ -180,6 +180,12 @@ public synchronized Record<T> read() throws Exception {
     public void close() {
         if (sourceTask != null) {
             sourceTask.stop();
+            sourceTask = null;
+        }
+
+        if (offsetStore != null) {
+            offsetStore.stop();
+            offsetStore = null;
         }
     }
 
diff --git a/pulsar-io/kafka-connect-adaptor/src/main/java/org/apache/pulsar/io/kafka/connect/PulsarOffsetBackingStore.java b/pulsar-io/kafka-connect-adaptor/src/main/java/org/apache/pulsar/io/kafka/connect/PulsarOffsetBackingStore.java
index b1338f837bb49..495c8b9c194c0 100644
--- a/pulsar-io/kafka-connect-adaptor/src/main/java/org/apache/pulsar/io/kafka/connect/PulsarOffsetBackingStore.java
+++ b/pulsar-io/kafka-connect-adaptor/src/main/java/org/apache/pulsar/io/kafka/connect/PulsarOffsetBackingStore.java
@@ -158,12 +158,19 @@ public void start() {
 
     @Override
     public void stop() {
+        log.info("Stopping PulsarOffsetBackingStore");
         if (null != producer) {
+            try {
+                producer.flush();
+            } catch (PulsarClientException pce) {
+                log.warn("Failed to flush the producer", pce);
+            }
             try {
                 producer.close();
             } catch (PulsarClientException e) {
                 log.warn("Failed to close producer", e);
             }
+            producer = null;
         }
         if (null != reader) {
             try {
@@ -171,7 +178,10 @@ public void stop() {
             } catch (IOException e) {
                 log.warn("Failed to close reader", e);
             }
+            reader = null;
         }
+
+        // do not close the client, it is provided by the sink context
     }
 
     @Override