Getting Access Denied on $out to s3 on Trigger

Hello, I’m trying to use Atlas Data Lake & Trigger to export some documents daily to an s3 bucket. I have followed these two guides ( How to Automate Continuous Data Copying from MongoDB to S3 and another guide titled “MongoDB Atlas Data Lake Tutorial: Federated Queries and $out to AWS S3” - cannot link because I can only post two links as a new user) and checked the documentations if I’m missing anything. I have set a trigger (currently disabled) on the Atlas UI and when I manually run it, it gives me this error:

which I believe is similar to the error in this post: Unauth Error on Moving Data from DataLake to S3
I also have the read and write permissions in AWS IAM for Atlas for the bucket. I appreciate the help about how I can debug this.