how to add consumer to existing kinesis stream from java MS?

Hi,

If you're using 'LATEST' iterator type, the consumer starts reading new data records from the most recent point onwards and does not read the data records written prior to it. For reading older data, you may consider using a 'TRIM_HORIZON' shard iterator type, which starts reading the oldest data record in the shard.

The above also holds true when using 'Data viewer' in Kinesis Streams via AWS Console.

[+] https://docs.aws.amazon.com/streams/latest/dev/data-viewer.html#:~:text=Latest%3A%20Show%20records%20just%20after%20the%20most%20recent%20record%20in%20the%20shard%2C%20so%20that%20you%20always%20read%20the%20most%20recent%20data%20in%20the%20shard