The company, Courier, experienced a sudden increase in their AWS billings that far exceeded typical benchmarks. The issue was discovered to be data insights tools sending an unexpectedly large volume of data. To resolve the problem, the team had to conduct a deep dive into how AWS billing works and identify the location of the "firehose" of data. With the help of CloudZero, a company providing cost analysis services, they were able to gain insights into their costs and make necessary adjustments. They found that high volumes of log data from Datadog were contributing significantly to their costs, particularly in CloudWatch and X-ray. By removing the unnecessary layers and optimizing their configuration, the team was able to reduce their costs and bring them back under control. The experience highlighted the importance of understanding one's ecosystem and use cases when using serverless technologies like AWS. It also emphasized the need for monitoring and analysis to optimize costs and performance.