WIndow operator in siddhi query are failing

[SMART2016]

Hi,

Below query when run is failing with error:
Error on sending events [Event{timestamp=1641985535389, data=[4, 4320918970, 2, resource, aws_S3, stackidentitytest.com, stackidentitytest.com, True, S3FullControlAccess, [], 2022-01-12 16:35:35], isExpired=false}] in the SiddhiApp 'c089377c-4eda-4adb-b925-a315f5bcd20f'
org.apache.flink.streaming.runtime.tasks.ExceptionInChainedOperatorException: Could not forward element to next operator

Query:
from StockStream#window.lengthBatch(10)
select list:collect(symbol) as stockSymbols
insert into OutputStream;