Unable to auto-refresh data using AWS Gateway API

Hi,

I an trying to enable secure access to data in S3 from Power BI. I am using AWS Gateway API to access csv files in S3 bucket.

I am able to pull the data in locally, but I get an error when I try to refresh it after publishing it. I have tried to use relative path and the API is configured to return 200 code when accessing the public root. However, it still errors out when I try to refresh the data in the cloud. I get an error that says that the first column of the dataset cannot be found, which means it's probably returning an empty dataset during refresh. How can I fix this?

This is the beginning of my code in the query editor: 

let
Source = Csv.Document(Web.Contents("https://url",
[Headers=[#"X-API-KEY"="XXXXX"],
RelativePath="/folder%2Ftest.csv"]),
[Delimiter=",", Columns=15, Encoding=1251, QuoteStyle=QuoteStyle.None])