Kafka credit has grown exponentially within 4 days of usage

5 days ago, i started using Aws services for my college project where i was subscribed to services such as Kafka, IAM, EC2 and redshift. Today I was checking on the Aws 's stats for billing, only to found out that my service charges for Amazon Managed Streaming for Apache Kafka (MSK) has peaked around at 60$. It doesn't seem plausible to me that within 4 days i got to this amount. My data providing applications weren't active all the time, perhaps it's some failed request to data ingestion Kafka side which might be inflating the bill. I request you to please check on this issue and provide me a way to resolve this.