Firehose delivery stream not writing to s3

I created a datastream connected to api gateway and a firehose delivery stream connected to the datastream that writes to an S3 bucket. There is nothing being writtten to S3 irrespective of the data successfully being received in data stream. No error logs, and the dashboards show that there are no records written to s3. Need help in trouble shooting. Appreciate any help.

Thanks, Haripriya