Can't sink BigTable Connector. Unexpected error occurred with connector

Confluent Cloud
1

Hi, I’m new for confluent platform and Kafka streaming. I would like to sink the topic to Bigtable in GCP. But, I can’t build the BigTable connector successfully. But, with the same topic, I can build the big query connector success.

BigTable Connector Error: Unexpected error occurred with connector. Confluent connect
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BigTable Config
Topic Name: page_events_agg
Input Kafka record value format: JSON
Input Kafka record key format: JSON

Query when I create the topic

CREATE OR REPLACE TABLE  page_events_agg_table
WITH (KAFKA_TOPIC='page_events_agg_table',KEY_FORMAT='JSON', VALUE_FORMAT='JSON', PARTITIONS=1) 
AS
SELECT 
  SPLIT(DETAIL,'__')[2] ROW_KEY
, AS_VALUE(SPLIT(DETAIL,'__')[2]) PAGE
, sum(total_spending/1000/60) TOTAL_TIME_SPENDING_M
FROM customer_page_spending_stream
WINDOW TUMBLING ( SIZE 5 MINUTES ) 
GROUP BY SPLIT(detail,'__')[2]
EMIT CHANGES;

Additional: If I remove the key format when creating the topic. I got the Key Format Type with KAFKA. I can build the Bigtable connector success, but I got the message in DLQ instead. It shows this error.

"org.apache.kafka.connect.errors.DataException: Converting byte[] to Kafka Connect data failed due to serialization error

Can anyone help/suggest me to solve it. TT

Thank you so much for all help.